Planning

Minutes HILLINGDON PLANNING COMMITTEE 5 November 2025 Meeting held at Committee Room 5 - Civic Centre Committee Members Present: Councillors Henry Higgins (Chair), Adam Bennett (Vice-Chair), Keith Burrows, Roy Chamdal, Elizabeth Garelick, Jagjit Singh and Raju Sansarpuri LBH Officers Present: Roz Johnson – Planning Services Manager Eoin Concannon – Planning Team Leader Ed Laughton – Area Planning Service Manager (C&S) Haydon Richardson – Deputy Team Leader Dr Alan Tilly – Transport & Aviation Team Manager Natalie Fairclough– Legal Advisor Anisha Teji – Democratic Services 98. APOLOGIES FOR ABSENCE (Agenda Item 1) There were no apologies for absence. 99. DECLARATIONS OF INTEREST IN MATTERS COMING BEFORE THIS MEETING (Agenda Item 2) Councillor Henry Higgins declared a non-pecuniary interest in agenda item 6 as he had met the applicant during a local Ward Surgery. He left the room during discussion of agenda item 6. 100. TO RECEIVE THE MINUTES OF THE PREVIOUS MEETING (Agenda Item 3) RESOLVED: That the minutes from the meeting on 2 October 2025 be approved. 101. MATTERS THAT HAVE BEEN NOTIFIED IN ADVANCE OR URGENT (Agenda Item 4) None. 102. TO CONFIRM THAT THE ITEMS OF BUSINESS MARKED PART I WILL BE CONSIDERED IN PUBLIC AND THE ITEMS MARKED PART II WILL BE CONSIDERED IN PRIVATE (Agenda Item 5) It was It was confirmed that all items would be heard in Part I. that all items would be heard in Part I. 103. LAND TO THE REAR OF 18 MOOR PARK ROAD, NORTHWOOD - 74971/APP/2025/780 (Agenda Item 6) Erection of 1no. detached bungalow, with associated parking (including installation of new vehicular crossover), landscaping, cycle parking and refuse storage. Officers introduced the application, took Members through the plans and outlined the application history. A recommendation for approval was made. A petitioner in objection to the application addressed the Committee, noting that the proposal would harm the street pattern by introducing a lone dwelling that conflicted with the existing layout. The petitioner stated that previous applications for similar development had been refused and argued that comparisons with 1a Grove Road were unjustified, as that case involved replacing a bungalow with a detached property in keeping with surrounding housing. The petitioner highlighted that the Planning Inspector had previously ruled the site unsuitable, stating that such development would cause unacceptable harm to the street scene. Further objections included loss of garden land contrary to Policy DMH6, overlooking and loss of privacy for neighbouring properties, and a negative impact on the area’s spacious and open character. The petitioner highlighted that approval would set a harmful precedent and urged the Committee to refuse the application. The agent addressed the Committee and commended officers for the well-written report. It was noted that the applicant had worked closely with officers to resolve issues raised in previous applications. It was explained that the revised scheme differed significantly in scale, design, and layout, and its impact on the character of the area had been carefully considered. Responding to concerns raised by the Planning Inspector, the agent highlighted that the proposal included a substantial reduction in size, enhanced landscaping, and a setback from the road, which together ensured minimal impact on the street scene. It was noted that the character of the road had evolved since the earlier scheme was assessed. The design was said to have been prepared to avoid harm to visual amenity and highway safety. The agent emphasised that the proposed bungalow was located within a residential area, complied with officers’ requirements, and made efficient use of the site. It was clarified that planning policy did not prohibit development on garden land, provided it was carried out sensitively. The agent stated that objectors’ concerns had been fully addressed and reminded Members that planning decisions required a balance of competing considerations. The Committee was urged to approve the application, with the agent stressing that refusal should only occur where demonstrable and significant harm could be shown. In response to Members’ questions, the agent explained that after the appeal decision, a revised scheme was developed in consultation with officers. The new application addressed the Planning Inspector’s comments and was designed to avoid any harmful impact on the area’s character. During Committee discussions, officers explained that a larger two-storey dwelling would not have fitted appropriately within a rear garden. Under garden development policies, a single-storey dwelling was considered more proportionate and the reduction in size allowed for additional landscaping and biodiversity improvements. Officers noted that this scheme differed from previous proposals and that the bungalow design was suitable for the plot. Members acknowledged that this was back garden development and sought clarity on the Planning Inspector’s previous comments that any development would harm the street scene. They also queried whether conditions could prevent further development. Officers confirmed that the appeal decision had been considered however the revised scheme complied with policy DMH6. The reduced scale maintained local character and biodiversity. Each property was over 21 metres apart, protecting privacy and preventing overlooking and the single-storey design ensured no impact on lighting. Biodiversity net gain had increased on the site, making this proposal materially different from the appeal decision. Officers added that a condition removing permitted development rights was included and any future applications would be assessed at the time. The scheme contributed to housing needs, complied with planning policies and its scale had been significantly reduced. Officers advised that in their opinion refusal would likely be unsuccessfully defended at appeal. The Committee was assured that the inspector’s comments had been taken into account. Although Members empathised with the petitioner’s concerns, it was noted that the new application met policy requirements and that overturning the officer recommendation would be difficult. The recommendation was therefore moved, seconded, and, when put to a vote, five Members voted in favour and one abstained. RESOLVED: That the application be approved as per officer recommendation. 104. CLUB HOUSE, MIDDLESEX STADIUM, BREAKSPEAR ROAD, RUISLIP - 17942/APP/2024/2874 (Agenda Item 7) Construction of natural grass football pitches using imported soils approved for use by the Environment Agency. Proposals include rainwater harvesting scheme, extensive planting Officers introduced the application and took Members through the plans. It was noted that a typographical amendment would need to be made to condition 4 to read ‘ Prior to commencement of development and scheme for the provision of sustainable water management s hall be submitted to and approved in writing by the loca l planning authority.’ A recommendation for approval was made. With the prior permission of the Chair, Councillor Peter Smallwood addressed the Committee highlighting his strong support for the application. The applicant’s collaboration with Councillors , the Council and the Environment Agency was praised. The proposal was seen as vital for grassroots football, supporting community life, providing opportunities for all ages and preserving the legacy of Hillingdon Borough Football Club. It was noted that t he scheme enhanced sports provision, improved drainage and biodiversity and maintained Green Belt openness. The Committee welcomed the proposal as a positive community benefit. Questions were asked about construction timing and traffic impact. Officers c onfirmed completion within three planting seasons and explained that traffic increases during soil importation would be temporary and managed through a Construction Management Plan. Lighting was addressed, with a condition requiring further approval for floodlighting. The application was proposed, seconded, and unanimously approved. RESOLVED: That the application be approved as per officer recommendation subject to the minor typographical amendment to condition 4. 105. UNIT 2 RUISLIP RETAIL PARK, VICTORIA ROAD - 43510/APP/2024/3336 (Agenda Item 8) Officers introduced the application and took Members through the plans. A recommendation for approval and s106 legal agreement was made. The Committee welcomed the proposal, noting that the new unit would benefit the local area by creating business opportunities and jobs. In response to a question on the reduced contribution and sustainable measures, it was explained that the amount had been calculated us ing a detailed methodology considering benchmarks and site - specific constraints. Factors such as limited space, lack of tree planting, a secured travel plan, and no additional parking were taken into account. The contribution was confirmed as appropriate and reasonable, although a specific fig ure could not be provided as the proposal did not fit standard benchmarks. The officers’ recommendation, was moved, seconded, and when put to a vote, was unanimously agreed. RESOLVED: That the s106 legal agreement and application be approved as per officer recommendation. The meeting, which commenced at 7.00 pm, closed at 8.10 pm. These are the minutes of the above meeting. For more information on any of the resolutions please contact Anisha Teji on 01895277655 or ateji@hillingdon.gov.uk. Circulation of these minutes is to Councillors, Officers, the Press and Members of the Public.

Hillingdon Planning Committee – 16th December 2025 PART 1 – Members, Public & Press Report of the Head of Development Management and Building Control Planning Committee Report Case Officer: Ed Laughton 41573/APP/2024/2838 Date Application Valid: 28.10.24 Statutory / Agreed Determination Deadline: 31.10.25 Application Type: Full Ward: Heathrow Villages Applicant: Heathrow Airport Limited Site Address: Heathrow Airport Proposal: Enabling works to allow implementation of full runway alternation during easterly operations at Heathrow Airport including the creation of a new 'hold area' at the western end of the northern runway, the construction of new access and exit taxiways, the construction of an acoustic noise barrier to the south of Longford Village and temporary construction compounds. The proposed development is subject to an Environment Impact Assessment (Notice under Article 19 of the Town and Country Planning (Environmental Impact Assessment) Regulations 2017). Summary of Recommendation: GRANT planning permission subject to section 106 legal agreement and conditions Reason Reported to Committee: Required under Part 1 of the Planning Scheme of Delegation (Major application recommended for approval) Hillingdon Planning Committee – 16th December 2025 PART 1 – Members, Public & Press Summary of Recommendation: GRANT planning permission subject to the completion of a satisfactory section 106 legal agreement to secure the heads of terms set out below, and subject to the conditions as set out in Appendix 1. It is recommended that delegated powers be given to the Director of Planning and Sustainable Growth to grant planning permission subject to the following: A) That the Council enter into a legal agreement with the applicant under Section 106 of the Town and Country Planning Act 1990 (as amended) or any other legislation to secure the following: Noise Mitigation Updated noise assessment Prior to the commencement of easterly alternation operations, Heathrow Airport Ltd. (HAL) will provide to the Council (i) an updated noise assessment based upon the latest forecasts and associated route allocations for the current fleet and (ii) a map and list of properties (including addresses) which fall within Categories B, C, D1 and D2 and to which an offer will be made. Engagement Prior to the commencement of operations, HAL will provide details of how the property owners of Categories, A, B, C, D1 and D2, as well as the schools requiring insulation will be informed of the relevant eligibility and implementation criteria in accordance with a scheme agreed with the Council. Noise mitigation for residential properties Eligible properties • Category A: Any properties exposed to harmful ground noise and vibration from departure roll on runway 09L will be identified prior to commencement of operations and will be eligible for up to £10,000 towards the cost of mitigating the effects of noise induced vibration predicted as a result of the Development (in addition to any eligibility under HAL’s existing Quieter Neighbourhood Support scheme (QNS)). Hillingdon Planning Committee – 16th December 2025 PART 1 – Members, Public & Press • Category B: Properties forecast to be exposed to noise levels of 69 dB LAeq, 16hr and above as a result of the Development (and which do not already qualify for HAL’s existing Home Relocation Assistance Scheme (HRAS)) will be eligible for a sum comprising 1% of the unblighted sale price plus £10,000 up to a maximum of £20,000 to be paid on completion of the property sale. • Category C: Properties that become eligible for the QNS once the QNS boundary is updated to account for the Development will be eligible to receive the full noise insulation package up to £34,000 (unless where additional mitigation measures are required in exceptional circumstances) towards noise insultation costs. • Category D1: Properties forecast to be exposed to air noise levels of 60 to 63 dB LAeq, 16hr and an increase of 3dB or more as a result of the Development will be eligible to receive up to £12,000 towards noise insulation costs. • Category D2: Properties forecast to be exposed to air noise levels of 54 to 60 dB LAeq, 16hr and an increase of 3 dB or more as a result of the Development will be eligible to receive a fixed amount of £3,000 towards noise insultation costs. In respect of Category A, C and D1 properties, the actual amount to be offered by HAL will be determined following an independent survey and assessment. Schools insultation HAL will offer a package of bespoke insulation and ventilation measures of up to £2.5m per school to: • Littlebrook Nursery • Khosla House • Cranford Community College • Cedars Primary School Parks and Gardens Within 3 months from implementation of the planning permission, HAL will make a financial contribution to the Council of £250,000 (in total) towards the enhancement of Berkeley Meadows, Avenue Park and Cranford Park. Monitoring Hillingdon Planning Committee – 16th December 2025 PART 1 – Members, Public & Press Prior to commencement of easterly alternation, a monitoring plan will be agreed with the Council. The monitoring plan will set out how and when (annually) the Council will be informed of the progress of delivering the noise insulation measures outlined above (excluding Parks and Gardens). Dispute Resolution Prior to commencement of easterly alternation, a dispute resolution process will be agreed between HAL and the Council. Ground Noise and Vibration HAL will monitor actual ground noise and vibration levels impacted by Operations and use results to inform the development of the Ground Noise and Vibration Management Plan. The location and methodology for assessing ground noise and vibration will be agreed in writing alongside approaches to mitigation. Temporary Rehousing HAL will provide temporary rehousing to any occupied households for which the predicated construction noise levels exceed specified thresholds. Air Quality HAL will pay £100,000 to the Council as an air quality contribution to mitigate air quality impacts in Longford. Mitigation measures are to be identified in an Air Quality Action Plan for Longford (LAQAP) funded by HAL and produced by LBH. An Ultrafine Particles (UFP) Monitoring and Action Plan is to be secured. (Details related to this Heads of Term remain under discussion with the applicant at the time of writing and an update shall be provided to Members through the Planning Committee Addendum/at the Planning Committee). Noise Barrier Maintenance HAL shall undertake an inspection of the noise barrier on a biennial basis commencing one year after its completion. A report shall be prepared and submitted to the local planning authority setting out the findings of the inspection. Works to the noise barrier will be undertaken to ensure it maintains operational efficacy in line with the design parameters. Construction Noise HAL will submit a Section 61 application under the Control of Pollution Act 1974 for prior consent of the noise parameters for the construction period. Employment /Constructio n Training Scheme An Employment/ Construction Training Scheme secured to meet the objectives of the Council's Planning Obligations SPD. Hillingdon Planning Committee – 16th December 2025 PART 1 – Members, Public & Press Project Management & Monitoring Fee A Project Management and Monitoring Fee, equalling 5% of the total contributions to be paid under this agreement. B) That in respect of the application for planning permission, the applicant meets the Council's reasonable costs in preparation of the Section 106 agreement and any abortive work as a result of the agreement not being completed. C) That officers be authorised to negotiate and agree the detailed terms of the proposed agreement and conditions of approval. D) That, if the Legal Agreement has not been finalised within 9 months (or such other time frame as may be agreed by the Director of Planning and Sustainable Growth), delegated authority be given to the Director of Planning and Sustainable Growth to refuse planning permission for the following reason: 'The applicant has failed to mitigate the impacts posed by the proposed development (in respect of Noise and Vibration Impacts, Air Quality and Construction Training). The scheme therefore conflicts with Policy DMCI 7 of the Hillingdon Local Plan: Part 2 – Development Management Policies (2020); the adopted Planning Obligations Supplementary Planning Document (2014); Policy DF1 of the London Plan (2021); and paragraphs 56 -58 of the National Planning Policy Framework (2024).' E) That if the application is approved, that the permission is subject to the Conditions as set out in Appendix 1, subject to authorised negotiation by officers. 1 Executive Summary 1.1 This planning application seeks permission for the physical works required to the airfield at Heathrow Airport and supporting infrastructure to enable the implementation of full runway alternation between departures and arrivals during ‘easterly’ operations. The works will therefore facilitate the ending of the Cranford Agreement subject to further airspace change processes separate from the planning consenting regime. 1.2 These physical works would normally be covered by permitted development rights and as such would not require planning permission; however, since these works would facilitate a major change to the airport’s operations, they would give rise to likely signific ant environmental effects which removes permitted development rights. This triggers the need for an Environmental Impact Assessment (EIA) and this in turn means planning permission is required. In addition to the physical works and the likely significant environmental effects this report also considers the mitigation required and proposed for any detrimental impacts arising from the proposals. 1.3 The proposals do not relate to any increase in passenger numbers, and the application does not seek to raise or al ter the 480,000 air traffic movement cap Hillingdon Planning Committee – 16th December 2025 PART 1 – Members, Public & Press set as part of the Terminal 5 (T5) planning consent. Consequently, these proposals do not seek to enable any expansion in either the airport size or operational air traffic movements. However, the proposed works would theoretically increase potential operational capacity had that not otherwise already been capped. 1.4 The decision to end the Cranford Agreement is described in the main body of the report, as is the outcome of a prev ious application/appeal which concerned development for the purpose of implemen ting alternation. Works to implement alternation are, in consequence, supported in principle subject to securing appropriate mitigation and compensation. The following report sets out an appraisal of the package of mitigation and compensation solely in the context of ending the Cranford Agreement and enabling full al ternation when the airport operates easterly departures. Any future consideration of Heathrow Airport operations will be assessed separately and in accordance with the prevailing evidence base and in the context of benefits and disbenefits . This proposal is therefore considered on its own merits and without any prejudice to consideration of future Heathrow Airport related proposals. 1.5 As noted above, the proposed development is subject to an Environment Impact Assessment under the Town and Country Planning (Environmental Impact Assessment) Regulations 2017 [the EIA Regulations]. The planning application is supported by a substantial number of assessments and reports, including an Environmental Statement, to ensure that its effects are assessed appropriately. The environmental aspects included within the Environmental Statement are: i. Noise and Vibration; ii. Air Quality; iii. People and Communities; iv. Public Health; v. Landscape and Visual Impact Assessment; vi. Historic Environment; and vii. Biodiversity. 1.6 Overall, the Local Planning Authority considers that the Environmental Statement, as supplemented with additional information within the application submission , is sufficient to enable the Local Planning Authority to take a decision in compliance with the EIA Regulations,and it has been appropriately considered in reaching the recommendation to grant planning permission. 1.7 Heathrow Airport operates either on ‘easterly’ or ‘westerly’ operations, depending on the wind conditions. Aircraft normally take off and land into the wind, with the prevailing winds at Hea throw Airport coming from the west. Because airport operations are therefore dictated by climatic conditions the mode of operations varies. However, in general, westerly operations occur for approximately 70% of the time, with easterly operations occurring for about 30%. 1.8 During the day, the airport currently alternates (‘swaps’) the use of the two runways when on westerly operations, this provides local communities with Hillingdon Planning Committee – 16th December 2025 PART 1 – Members, Public & Press scheduled periods of respite. The present pattern means that from 06:00 until 15:00 one runway is used by landing ai rcraft and the other runway is used for departing aircraft, and then from 15:00 until the last departure the use of the runways for arrivals and departures is switched. This is known as runway alternation. 1.9 Runway alternation has not occurred routinely at the airport during easterly operations. Therefore, the northern runway is typically not used for scheduled easterly departures (over the community of Cranford) and the southern runway is typically not used for arrivals from the west. 1.10 During easterly operations, this means t hat most arriving aircraft land on the northern runway and most departures take off from the southern runway. This was originally due to the Cranford Agre ement, which was established in the 1950s to prevent aircraft from taking off over Cranford (located to the east of the Airport) when Heathrow was on easterly operations. The Cranford Agreement ended in January 2009 ; however, Heathrow Airport has not yet implemented full runway alternation during easterly operations. 1.11 Physical works are required to the airfie ld to enable the operational changes. Planning permission in respect of a previous scheme to introduce runway alternation was granted at appeal under application reference 41573/APP/2013/1288. However, that consent was not implemented and therefore in order to commence Easterly Alternation, the current application has been submitted. 1.12 A legacy of the Cranford Agreement is that the western end of the northern runway does not have the same extent of taxiways and holding areas as the other runway ends. The infrastructure proposed w ould provide the new runway access taxiways to enable regular and routine departures on the northern runway in an easterly direction (known as Runway 09L) with regular arrivals occurring on the southern runway (Runway 09R) from the west, when the wind is blowing from the east. 1.13 These works are relatively limited and relate to additional hardstanding areas for taxiways and hold areas to serve the western end of the northern runway, plus the construction of a noise barrier approximately 781m in length and between 5m to 7m in height near the village of Longford. The location of the works and further details are provided within Section 3 of this report. 1.14 If approved, the infrastructure works and the subsequent implementation of full runway alternation during easterly operations w ould not enable any increase in air traffic movements above the existing limit of 480,000 movements per year, conditioned as part of the Terminal 5 planning consent (application reference 47853/93/0246). 1.15 Subject to providing an appropriate package of mitigation measures, the principle of permitting the introduction of Easterly Alternation was established through the formal decision by government to end the Cranford Agreement, and Hillingdon Planning Committee – 16th December 2025 PART 1 – Members, Public & Press through the grant of planning consent by the Secretaries of State to the previous application, reference 41573/APP/2013/1288. 1.16 When the adverse impacts of the change in operations were examined at a planning inquiry as part of the appeal process for application reference 41573/APP/2013/1288, the Secretaries of State agreed with the Planning Inspector that the principle of allowing easterly alternation had been settled and that the questions to be addressed through an application related to “…whether or not the proposed mitigation and compensation measures for those likely to be affected by the proposals can be regarded as ‘appropriate’.” 1.17 The redistribution of flying activity around Heathrow would result in some people benefiting from a reduction in noise and overflying with new periods of respite introduced. However, some areas would be adversely affected. The fact that some adverse effects would arise from Easterly Alteration was known when the Cranford Agreement ended and when the Secretaries of State allowed HAL’s previous planning application in 2017. 1.18 The previous appeal decision is a material consideration in the determination of this application. One important reason why such previous decisions are capable of being material is that like cases should be decided in a like manner, so that there is consistency in public decision making. The current application is made for the purpose of introducing alternation, which is consistent with the previous application. Subject to the sufficiency and appropriateness of mitigation and compensation; and in the absence of a change of circumstances, the principle of development has been treated as established. The principles raised by the current application have already been examined through an independent inquiry and the proposals supported by the Secretaries of State. 1.19 This application therefore includes consideration of not only the physical works proposed to enable Easterly Alternation, but also whether the mitigation and compensation measures proposed through the planning process for those properties and individuals adversely impacted are appropriate. 1.20 The physical works proposed are all within the administrative boundary of the London Borough of Hillingdon. However, the wider impacts - in particular in relation to noise - of the proposed change, both positive and negative, in terms of aircraft movements and flight paths cover a much broader area. Therefore, an extended consultation process has been undertaken by the LPA for this planning application in terms of time, breadth and platforms utilised (in comparison with standard procedures). Full details are set out within Section 6 of this report. 1.21 The main adverse impacts of introducing Easterly Alternation relate to noise and air pollution. Noise 1.22 As stated above, the proposed development facilitates a change in the pattern of aircraft movements during easterly operations. Specifically, an increase in the Hillingdon Planning Committee – 16th December 2025 PART 1 – Members, Public & Press number of aircraft departing to the east on the northern runway and arriving on the southern runway during easterly operations, with commensurate decrease in the number of aircraft departing to the east on the southern runway and landing to the east on the northern runway during the same mode of operations. In turn, there would be changes in the noi se environment around the airport, caused by that change in operations. 1.23 The submitted Environmental Statement, including its assumptions and baseline data has been robustly interrogated and its findings reviewed by an independent noise specialist on behalf of the LPA. 1.24 The Noise Policy Statement for England (NPSE) sets the framework for managing noise impacts, aiming to avoid significant adverse effects, mitigate impacts, and improve quality of life. The relevant key thresholds are: - LOAEL (Lowest Observed Adverse Effect Level): Point where noise begins to cause measurable harm. - SOAEL (Significant Observed Adverse Effect Level): Higher threshold requiring strong mitigation. 1.25 The health impacts of aviation include links to noise sleep disturbance, chronic annoyance, cardiovascular disease, metabolic disorders, mental health issues, and cognitive effects in children. Annoyance is recognized as a health- related outcome, not just inconvenience. 1.26 The Civil Aviation Authority’s CAP 15 06 (Survey of Noise Attitudes) shows increasing sensitivity to aircraft noise and annoyance at lower levels than before. The World Health Organisation (WHO) highlights annoyance and sleep disturbance as critical health outcomes. 1.27 There is no adopted land use planning policy document that sets a confirmed level for either LOAEL or SOAEL. This application presents LOAEL at 51 dB LAeq,16hr and SOAEL at 63 dB LAeq,16hr, and as matters stand , these threshold levels have been accepted for the purpose of this application. 1.28 However, at a recent inquiry for Gatwick the Examiner challenged this, proposing lower thresholds for LOAEL at 45 dB and SOAEL at 54 dB. The Secretary of State indicated some support for this position but ultimately accepted 51 dB and 63 dB as LOAEL and SOAEL respectively. 1.29 A recent planning decision at Luton concur red with the final position at Gatwick of maintaining 51/63 dB daytime and 45/55 dB night-time. 1.30 In terms of overall noise impacts it is recognised that there will be benefits and disbenefits to residents in the areas surrounding Heathrow. Ending the Cranford Agreement improves equity in terms of predictable respite periods and would improve operational efficiency for HAL. The introduction of Easterly Alternation would result in approximately 62,100 people benefitting from reduced noise, Hillingdon Planning Committee – 16th December 2025 PART 1 – Members, Public & Press while 39,600 would experience an increase. It has been predicted that 15,400 people would face moderate adverse effects (>3 dB above LOAEL). 1.31 In addition to providing predictable respite periods, HAL have proposed the compensation measures set out in this report. It should be noted that the noise modelling is based on 2028 fleet assumptions, and should the application be approved that the legal agreement will require a reassessment be undertaken with updated fleet mix details before implementation. The updated noise assessment would include modelling for ‘with’ and ‘without’ Easterly Alternation scenarios, to be carried out by the Environmental Research and Consultancy Department (ERCD) as part of the UK Civil Aircraft Noise Contour Model (ANCON). The updated noise assessment shall be based on the latest forecasts and associated route allocations for the then current fleet. 1.32 In conclusion on noise, despite there being an evolving evidential position on aircraft noise and responses to it, the threshold levels proposed have been properly justified and are accepted for the purpose of this application. Subject to the further assessment discussed above being undertaken, H AL’s general mitigation package is considered adequate and consistent with precedent. Air Pollution 1.33 The site lies within an Air Quality Management Area and a designated Air Quality Focus Area, where air quality concerns ar e already significant. These factors have heightened scrutiny of the project’s potential impacts and the adequacy of proposed mitigation measures. 1.34 The proposed change in aircraft movements at ground level (i.e. through taxiing) as a result of implementing Easterly Alternation would not lead to a significant increase in air pollution. However, it would alter the distribution of air pollution and introduce greater pollution in some areas, with reduced air pollution in others. The increase in air pollution would most notably be to the village of Longford to the northwest of Heathrow, and critically to the north of the western end of the Northern runway. With a significant increase in flights taking off in an easterly direction from the Northern runway, there would be an increase in aircraft taxiing to the western end. 1.35 An initial review by the council’s Air Quality Specialist raised concerns regarding the omission of sensitive receptors and lack of ultrafine particle (UFP) assessment.HAL’s response to these concerns was to confirm that in their view the air quality impacts are negligible, with slight NO ΍ increases at a few properties. They argue that the Air Quality Neutral policy doesn’t apply to aviation emissions and disputed the damage cost calculations provided by the council’s Air Quality Specialist, noting that they were based solely on taxi -out emissions and did not account for reductions in taxi-in emissions. 1.36 The LPA’s position is that the impacts of the development are not insignificant, even if classified as “negligible” in the Environmental Statement. Small changes in pollutant levels are real, measurable, and contribute to cumulative exposure. Hillingdon Planning Committee – 16th December 2025 PART 1 – Members, Public & Press Therefore, the development must aim for air quality neutrality, and HAL are expected to follow the same mitigation and of fsetting standards as other major developments. 1.37 However, operational improvements proposed by the scheme should be factored in. HAL already operates extensive air quality action plans, which is a material consideration, but further mitigation is still required. Officers have secured a bespoke Air Quality Action Plan for Lo ngford, supported by £100,000 funding, alongside H AL’s existing commitments and operational benefits. This is considered an acceptable planning position. 1.38 In addition, officers have agreed with the applicant that HAL would fund at least one additional UFP monitor and that a UFP Monitoring and Action Plan will be secured through the s106 legal agreement , should the application be granted. Final details related to this Heads of Term remain under discussion with the applicant at the time of writing and an update shall be provided to Members through the Planning Committee Addendum/at the Planning Committee. Mitigation Proposals 1.39 HAL have proposed Noise and Air Quality Mitigation packages which officers consider to be broadly appropriate. 1.40 The headline details of the mitigation packages have been set out at the start of this report as the proposed Heads of Terms for Members of Planning Committee to consider. Officers have requested authority to negotiate the final details of the S106 legal agreement. Executive Summary Conclusion 1.41 Overall, the application seeks consent for the physical works that would enable Easterly Alternation following the end of the Cranford Agreement. The proposals would introduce respite to areas that currently receive none during easterly operations and wher e areas are likely to receive significant additional noise or air pollution then mitigation is proposed and would be secured through a legal agreement. 1.42 Due regard has been given to the comments received as part of the consultation process and it is concluded that the proposal complies with the Development Plan. Section 38(6) of the Planning and Compulsory Purchase Act 2004 states that planning applications should be determined in accordance with the Development P lan unless material considerations indicate otherwise. For the reasons outlined above and within the main body of the report, this application is considered to comply with the Development Plan overall and is recommended for approval, subject to securing the p lanning conditions set out in Appendix 1 and a Section 106 legal agreement with the Heads of Terms set out above. Hillingdon Planning Committee – 16th December 2025 PART 1 – Members, Public & Press 2 The Site and Locality 2.1 The application site is Heathrow Air port, the United Kingdom’s largest and busiest airport, located approximately 14 miles (23 km) west of Central London. It serves as a major international gateway and is an important component of the UK’s transport infrastructure, supporting national and international connectivity, cargo logistics, and economic activity. 2.2 Heathrow Airport is located in the south of the borough on the boundaries with Hounslow, Spelthorne, Slough and Buckinghamshire Local Planning Authorities. The Airport occupies approximately 1,227 hectares (ha) of land and operates two parallel runways, with four operational terminals. The existing infrastructure is comprised of the hardstanding runways, terminal buildings, taxiways, aprons, auxiliary buildings and airfield grassland. 2.3 In 2019, Heathrow Airport handled over 80 million passengers, though this figure saw temporary reductions due to the COVID -19 pandemic. As of 2024, it has returned to pre-pandemic levels of passenger numbers. The Airport operates 24 hours a day, seven days a week. There are circa 650 aircraft arrivals and 650 departures every day at the Airport, with the number of Air Transport Movements (‘ATMs’) capped at 480,000 movements per annum, as a condition of the T5 planning permission granted in 2004 (application reference 47853/93/0246). A summary of the existing infrastructure within the airport is set out below: 2.4 1. Runways: the northern runway (known as 09L/27R) with a length of 3,902 metres and the southern runway (known as 09R/27L) of 3,660 metres, both lie east/west in their orientation. 2.5 2. Terminals: the Airport has four terminals operating where passengers arrive at and depart from the Airport. Terminal 1 (T1) closed in 2015. Terminal 2 (T2) and Terminal 3 (T3) form a cluster of terminal buildings known as the Central Terminal Area (‘CTA’) which sits in the ce ntral area of the Airport, between the northern and southern runways. Terminal 4 (T4) lies to the south of the airport and Terminal 5 (T5) lies at the western end of the airport between the runways. 2.6 3. Taxiways: the Airport has a taxiway network used by aircraft to circulate between terminals and the runways under the guidance of Air Traffic Controllers. The taxiway network comprises four parall el taxiways (two serving each of the runways), which are linked by cross field taxiways. There are also taxiways south of the southern runway, including one parallel taxiway, connecting T4 and the cargo area to the rest of the Airport. Runway links, including exit taxiways and Runway Access Taxiways (‘RATs’), connect the parallel taxiways to the runways themselves and are used by aircraft entering and exiting the runways. More minor taxiway links and cul -de-sac taxi lanes connect all the taxiways to the aircraft stands. 2.7 4. Aprons: are used for the parking of ai rcraft, refuelling, and the loading and unloading of passengers and freight. Each terminal building at Heathrow has its Hillingdon Planning Committee – 16th December 2025 PART 1 – Members, Public & Press own aprons. Additionally, there is a dedicated cargo apron in the south of the Airport for freight aircraft and maintenance aprons in the east of the Airport. 2.8 5. Ancillary facilities: are designated to support the operation and maintenance of the Airport. These include maintenance and repair facilities, warehousing and cargo storage facilities and other airport operational land (such as surface water pollution control, balancing ponds, construction compounds for ongoing work, in –flight catering facilities, air traffic control, baggage and parking for service equipment). These are located across the Airport. 2.9 The Airport is accessible by car, from the M4 and M25 motorways which are located to the north and west respectively. The highway network links the Airport to its surroundings through perimeter roads. The perimeter road immediately to the north of the Airport is called Wright Way. There are eleven car parks for short stay and long stay located within and adjacent to the Airport’s boundary, including the POD parking at T5, which allows passengers to get to and from the terminal in a driverless, electric transit solution. 2.10 Heathrow Airport is also very well connecte d by public transport, including the Heathrow Express (from London Paddington), the Elizabeth line (from central London), the London Underground (via Piccadilly line). A rail -air bus link also provides regular connections by bus and coaches between Heathrow Airport and National Rail stations at Feltham, Guil dford, Reading, Watford Junction and Woking, to supplement a network of bus services. 2.11 The Duke of Northumberland’s River flows around the western boundary of the airport and encloses the T5 POD car park to the northwest. 2.12 The surrounding area is characterised by a mixed use of hotels, office space, industrial, commercial and residential uses. There are several communities bordering Heathrow’s perimeter including: • To the north: Longford, Harmondsworth, Sipson, Harlington. • To the east: Cranford and Hatton. • To the south: West and East Bedfont, Stanwell and Stanwell Moor. • To the west: Colnbrook, Poyle and Windsor. 2.13 Whilst the immediate surroundings are urban areas, to the north-west, south- west and west, the Airport setting is also characterised by land within the Green Belt or other open areas i.e. more rural in character where development is more restricted. Significant to the determination of this application in terms of air quality impacts, to the north west of the Airport li es the village of Longford. Longford is a linear village, laid out either side of the Bath Road. The centre of the village is a Conservation Area, designated in 1988. Hillingdon Planning Committee – 16th December 2025 PART 1 – Members, Public & Press Figure 1: Ariel view of Heathrow Airport 2.14 The physical works that are proposed in the current application are to be undertaken in the western half of the airfield as set out in the Location Plan below. Figure 2: Location Plan (application site edged red) Hillingdon Planning Committee – 16th December 2025 PART 1 – Members, Public & Press 2.15 The proposed amendments to provide the two new Runway Access Taxiways (RATs) to the western end of the Northern Runway would be within an area that currently provides an existing RAT, aprons and open grassland. Figure 3: Photo of the western end of the northern runway and existing RATS Figure 4: Photo of the western end of the northern runway and existing RATS Hillingdon Planning Committee – 16th December 2025 PART 1 – Members, Public & Press Figure 5: Photo of the southern runway and existing RATS with excess hardstanding 2.16 On the line of the proposed noise barr ier (discussed in greater detail in Section 3 of this report below) there is currently an existing wooden noise barrier, approximately 3.0m in height, that runs parallel to Wright Way, the Western Perimeter Road and th e Duke of Northumberland River. The existing noise barrier finishes west of the T5 Pod Car Park where there is a gate access point to the Twin Rivers 1 maintenance track. The access gate is a palisade fence type construction with no noise barrier pr operties. The majority of the boundary around the T5 POD car park is fenced, with sections of both wooden and wire mesh fence construction approximately 2.0 to 3.0m in height. ϭdŚĞƵŬĞŽĨEŽƌƚŚƵŵďĞƌůĂŶĚZŝǀĞƌĂŶĚƚŚĞ>ŽŶŐĨŽƌĚZŝǀĞƌ͕ďŽƚŚƐĞĐƚŝŽŶƐŽĨĂƌƚŝĨŝĐŝĂůǁĂƚĞƌǁĂLJĚŝǀĞƌƚŝŶŐǁĂƚĞƌ ĨƌŽŵƚŚĞZŝǀĞƌŽůŶĞƚŚĂƚƌƵŶŝŶƉĂƌĂůůĞůĨŽƌƐĞĐƚŝŽŶƐĂĚũĂĐĞŶƚƚŽ,ĞĂƚŚƌŽǁ͛ƐďŽƵŶĚĂƌLJ͘ Hillingdon Planning Committee – 16th December 2025 PART 1 – Members, Public & Press Figure 6: Image of the existing noise barrier location adjacent to the Duke of Northumberland River Hillingdon Planning Committee – 16th December 2025 PART 1 – Members, Public & Press Figure 7: Image of the proposed route for the noise barrier following the Duke of Northumberland River Hillingdon Planning Committee – 16th December 2025 PART 1 – Members, Public & Press Figure 8: Image of the existing noise ba rrier below the existing elevated POD route Figure 9: Image of the proposed route fo r the noise barrier following the Two Rivers Hillingdon Planning Committee – 16th December 2025 PART 1 – Members, Public & Press Figure 10: View from the Two Rivers towards the south Figure 11: View of the existing noise barrier towards the T5 POD car park Hillingdon Planning Committee – 16th December 2025 PART 1 – Members, Public & Press Figure 12: View across the Two Rivers Figure 13: View of existing noise barrier from within the T5 POD Car Park Hillingdon Planning Committee – 16th December 2025 PART 1 – Members, Public & Press Figure 14: View of existing noise barrier from within the T5 POD Car Park 2.17 The application site covers a significant area and is predominantly located within Flood Zone 1. Part of the site and the wider area is within the Heathrow Airport Public Safety Zone. A Nature Conservation Site of Metropolitan or Borough Grade I Importance intersects the location of the proposed noise barrier and an Archaeological Priority Area also intersects the site’s red line bound ary. There are no Tree Preservation Orders that cover the site. Hillingdon Planning Committee – 16th December 2025 PART 1 – Members, Public & Press Figure 15: Policy Constraints Map 2.18 Directly adjacent to a significant sect ion of the proposed noise barrier is designated as green belt (see image below). The barrier is not proposed to be located within the designated green belt, however when the previous application was considered, the T5 POD car park was part of the Green Belt. The Green Belt boundary has changed in the immediate vicinity of the T5 POD car park as a result of the adoption of the Hillingdon Local Plan Part 2: Site Allocations and Designations (adopted January 2020) . The change was justified as follows: the area previously in the Green Belt was “separated from the adjoining main Green Belt area in the Colne Valley by the Duk e of Northumberland’s River. Longford Green has been fully developed and is now occupied by the Heathrow Business Class Car Park. As such, both sites do not meet any of the purposes of including in the Green Belt as identified in the NPPF at paragraph 80…” Hillingdon Planning Committee – 16th December 2025 PART 1 – Members, Public & Press Figure 16: Map showing Green Belt boundary at Longford 3 Proposal 3.1 The description of development proposed is as follows: 3.2 “Enabling works to allow implementation of full runway alternation during easterly operations at Heathrow Airport including the creation of a new 'hold area' at the western end of the northern runway, the construction of new access and exit taxiways, the construction of an acoustic noise barrier to the south of Longford Village and temporary construction compounds.” 3.3 It is important to note that the plann ing application is for the physical works to enable Easterly Alternation to come into full operation. Therefore, this section of the report will focus on details of the physical works proposed first, before detailing what Easterly Alternation me ans in terms of how Heathrow Airport operates. The impacts of Easterly Alternation operations are then discussed within the body of the report, along with the effects from the physical proposals. Hillingdon Planning Committee – 16th December 2025 PART 1 – Members, Public & Press Figure 17: Aerial photograph showing location of proposed Noise Barrier and new access ways Airfield Proposed Infrastructure 3.4 The scale of the proposed airfield infrastructure works is relatively limited. It comprises a number of alterations to t he pavement areas of the airfield around the northern and southern runways. These alterations include additional taxiway infrastructure in the north-west corner of the airfield to provide additional capacity to allow departing aircraft to efficiently access the Northern Runway. This would form part of the Northern Runway’s Runway Hold Area (‘RHA’). 3.5 To offset the increased new taxiway pavement area and to ensure for drainage purposes that the works do not increase th e overall extent of impervious area, redundant airfield pavement w ould be removed and reinstated as grass areas near the Southern Runway of the airfield. Figure 18: Existing Western End of Northern Run Hillingdon Planning Committee – 16th December 2025 PART 1 – Members, Public & Press Figure 19: Proposed layout for the western end of Northern Run 3.6 Currently the Northern Runway has one main Runway Access Taxiway (RAT), which is located at the western end of the runway. There is a second RAT approximately 550m east, however accessing the runway via this route results in a shorter runway length being available, which limits the airports operational performance. 3.7 When compared to the other three run way ends on Heathrow’s airfield, the western end of the northern runway has less infrastructure, including less taxiway routes onto the runway. At present there are a minimum of three RATs provided on each of the other runway ends. This is a legacy of the northern runway not being routinely used for take -offs to the east. All the other three runway ends on Heathrow’s airfield are accessible via two or more non-disrupted taxiway routes within the RHAs, i.e. ta xiway routes that are not adjacent to aircraft stands and need to provide additional capacity for stand access and push back manoeuvres. 3.8 The main purpose of providing additional taxiway infrastructure in the north-west corner of the airfield is to provide additional capacity to allow departing aircraft to access Runway 09L more easily. The additional infrastructure would form part of the 09L Runway Hold Area (RHA). A key aim of the proposed layout is to provide comparable performance for the 09L RHA compared to Heathrow’s other runway ends, including providing an efficient and reliable taxiway network with adequate resili ence and no single p oints of failure. This includes providing additional routes onto the runway via new RATs, and developing a taxiway layout that accommodates the ingress and egress routes onto the stands located on the north face of Terminal 5a. Hillingdon Planning Committee – 16th December 2025 PART 1 – Members, Public & Press 3.9 The proposed layout consists of the following elements: - Three parallel taxiways, parallel to the runway centreline. The two most northern parallel taxiways would primarily be used as part of the runway hold area. The third, most southern parallel taxiway would primarily be used to provide access and egress from the existing aircraft stands on the north side of the T5a terminal. - A taxiway link connecting the three parallel taxiways. - Two new Runway Access Taxiways (R ATs), which would provide a taxiway route for aircraft departing from Runway 09L. Note these RATs would be used in parallel with the existing RAT at the westernmost end of the northern runway 3.10 The layout of the new taxiways is in a ccordance with minimum clearances as required by the Civil Aviation Authority (CAA) standards. The area would be operated by air traffic controllers who w ould utilise the network of parallel taxiways, taxiway links and RATs, to pr ovide the most efficient and safest sequence for the departing aircraft at the same time as providing access to and from the T5a stands. 3.11 Since the previous 2013 planning application, changes in airfield design standards, specifically a reduction in the minimum clearance required between a taxiway and runway, has meant it is viable to provide three parallel taxiways within the 09L RHA. This has the significant advantage that a taxiway can provide access to and egress from the aircraft stands on the north side of T5a separate to the runway hold taxiways. This subsequently meant the operational environmental impacts associated with queuing aircraft, such as noise and air quality, were reduced and safety improved since the 2013 proposal. 3.12 A total length of 4,235m of new taxiway centrelines is proposed to be provided, with a total area of 35,000m2 new taxiway pavement being constructed. To offset the increase in new taxiway pavement area, 38,800m2 of redundant airfield pavement is proposed to be removed and reinstated as grass area. Out of the 38,800m2 of redundant pavement to be removed, 13,650m2 w ould be within the footprint of the western end of the northern runways RHA and 25,150m2 would be located near the southern runway, on the airfield. All of the redundant pavement removed would be within the same surface water drainage catchment area. Hillingdon Planning Committee – 16th December 2025 PART 1 – Members, Public & Press Figure 20: Redundant pavement for reinstatement with grass (southern runway) 3.13 The majority of the new airfield pavement would be constructed from Pavement Quality Concrete (PQC). RAT pavement within the runway strip, which is defined as 105m from the runway centreline, would be constructed from composite pavement. Composite pavement is constructed from a concrete base and overlaid with asphalt. Therefore, areas of composite pavement would be asphalt at the finished ground level. This is consistent with new RATs built on Heathrow’s airfield today. 3.14 Aeronautical Ground Lighting (AGL) would be installed along the centreline and stop bar positions of the new taxiways. The spacing of the centreline lights is typically 60m along straight sections of taxiways and 30m around curved sections and junctions. The AGL would be illuminated during periods of low visibility and non-daylight operational hours. The presence and use of AGLs is consistent with the airfield today. 3.15 The new taxiway infrastructure would be limited to gradients of 1.5% and below and therefore would appear ‘flat’. The new taxiways would tie- into the existing taxiway network at the existing levels. 3.16 There would be no additional floodlight or airport perimeter lighting provided as part of the proposed scheme. 3.17 Where redundant airfield pavement is removed, it would be reinstated to grass areas. The grass would be a specific seed mix to reduce any bird attraction. The appearance of the grass will be compar able with grass areas on Heathrow’s Hillingdon Planning Committee – 16th December 2025 PART 1 – Members, Public & Press airfield today. Areas of grass which would be exposed to aircraft blast would have blast treatment. Proposed Noise Barrier 3.18 A noise barrier is proposed to the south of the village of Longford. The noise barrier would range between 5m to 7m in height and be approximately 781m in length. The proposed 5m height noise barrier alignment would be in total 235m in length and the proposed 7m section would be 546m long. For part of its length, it would replace an existing acoustic barrier running alongside Wright Way and a close boarded timber fence which marks the boundary of the T5 POD car park. Figure 21: Existing Fence/Noise Barrier – Site Layout 3.19 Currently there is an existing wooden noise barrier, approximately 3m in height, that runs parallel to Wright Way, the Western Perimeter Road and the Twin Rivers. The noise barrier finishes west of the T5 Pod Car Park where there is a gate access point to the Twin Rivers maintenance track. The access gate is a palisade fence type construction with no noise barrier properties. The majority of the boundary around the T5 POD car park is fenced, with sections of both wooden and wire mesh fence construction approximately 3m in height. Outside of the T5 POD car park boundary, adjacent to the fence on the non -car park side is areas of vegetation including trees. 3.20 The existing noise barrier is proposed to be replaced by the proposed enhanced barrier, the details of which are set out below. Hillingdon Planning Committee – 16th December 2025 PART 1 – Members, Public & Press Figure 22: Proposed Noise Barrier General Arrangement 3.21 The proposed barrier would extend parallel to Wright Way and the Western Perimeter Road, and around the West and North boundary of the T5 Business Car Park (T5 POD Parking). The primary function of the noise barrier is to provide noise mitigation to properties within Longford village against ground noise at the northern runway end. The barrier would be constructed before other works and would limit noise in Longford from construction works on the airfield. 3.22 In addition to providing noise mitigation, the noise barrier would also act as a security boundary to the Twin Rivers and T5 POD parking. The noise barrier would replace existing fencing adjacent to the Twin Rivers. An access gate would be provided within the noise barrier to provide maintenance access to the Twin Rivers site. The access gate wou ld be secured and only accessible to authorised users. The gate would be located on the existing maintenance access track, and therefore maintenance access to the Twin Rivers site would be maintained. 3.23 As stated above, the noise barrier would be between 5m and 7m in height. It is proposed that the top 2m and 4m respectively of the barrier would be constructed from transparent Perspex type material. The bottom 3m of barrier would be constructed from non-transparent material, with an external wooden finish. 3.24 Should the planning application be granted, it is proposed (and agreed by the applicant), that a condition be attached to the consent requiring full details of the barriers proposed construction and materials. Details of maintenance will also be required, along with what measures will be used to avoid birds flying into the upper transparent section of the barrier. This may include lines within the material that are visible to birds, thus alerting them to the presence of the barrier, but are not clear to the human eye from anything other than a very close distance. Hillingdon Planning Committee – 16th December 2025 PART 1 – Members, Public & Press Figure 23: Section of proposed 5m high barrier adjacent to Duke of Northumberland River Figure 24: Section of proposed 7m high barrier adjacent to T5 POD Parking 3.25 No dedicated lighting is proposed to be provided as part of the noise barrier. However, the existing street lighting whic h runs parallel to the existing noise barrier may be removed and re -provided to facilitate construction. The existing lighting level is not proposed to be increased. Hillingdon Planning Committee – 16th December 2025 PART 1 – Members, Public & Press 3.26 Ground levels of the areas surrounding the noise barrier would remain unchanged. Around the T5 POD car park, the noise barrier would follow the alignment of the existing fence. Theref ore, the existing vegetation and trees beyond the barrier would be retained where possible. Where viable, the spacing and location of post foundations would be adjusted to avoid tree roots. 3.27 A noise barrier was also consented under the previous 2013 planning application scheme, the current proposal follows the same alignment except for adjacent to the Twin Rivers maintenance track, directly west of the T5 POD car park access, where it has been adjusted to allow the proposed scheme to sit outside of the Green Belt boundary. 3.28 Since the previous 2013 planning appl ication, there have been some minor changes to the height at which structures can be built around the airport without impacting air safety (known as safeguarding surfaces) associated with the airport and, in particular, those at the location of the noise barrier have increased in height. As a result, it is now feasible to construct a higher noise barrier without impeding safeguarding surfaces. Noise modelling was completed by the applicant prior to submission to assess the impact of a 7m high noise barrier compared to a 5m high noise barrier, wi th the 7m barrier found to be more effective. Above 7m in height, the noise modelling undertaken indicated no significant additional benefit. 3.29 A safeguarding check has been undertaken to ensure the proposed noise barrier does not infringe any of the airport’s Obstacle Limitation Surface (OLS) 2 and Instrument Flights Procedure (IFP) 3 safeguarding surfaces in accordance with CAA requirements. 3.30 The application submission includes a full Visual Impact Assessment and Viewpoint Analysis, with supporting CGI images of how the barrier would look if constructed. Summer and winter images are provided and discussed in more detail in Section 7 of this report. Easterly Alternation 3.31 The physical works set out above are requ ired to Heathrow Airport’s airfield in order to enable the implementation of full runway alternation between departures and arrivals during ‘easterly’ operations. 3.32 The Airport operates two parallel runways, the northern runway (which is called Runway 09L/27R), and the southern runway (Runway 09R/27L) predominantly in segregated mode (i.e. with one runway used for landings whilst the other is ϮdŚĞKďƐƚĂĐůĞ>ŝŵŝƚĂƚŝŽŶ^ƵƌĨĂĐĞ;K>^ͿŝƐĂĚĞĨŝŶĞĚǀŽůƵŵĞŽĨĂŝƌƐƉĂĐĞĂďŽǀĞĂƐĞƚŽĨƐƵƌĨĂĐĞƐĚĞƐŝŐŶĞĚƚŽƉƌŽƚĞĐƚ ĂŝƌĐƌĂĨƚĨůLJŝŶŐŝŶǀŝƐƵĂůĐŽŶĚŝƚŝŽŶƐ͘/ƚƉƌŝŵĂƌŝůLJĞŶƐƵƌĞƐƚŚĂƚŽďƐƚĂĐůĞƐĚŽŶŽƚŝŶƚƌƵĚĞŝŶƚŽƚŚĞĂŝƌƐƉĂĐĞƌĞƋƵŝƌĞĚĨŽƌ ƐĂĨĞĂŝƌĐƌĂĨƚŽƉĞƌĂƚŝŽŶƐ͕ƉĂƌƚŝĐƵůĂƌůLJĚƵƌŝŶŐƚĂŬĞŽĨĨĂŶĚůĂŶĚŝŶŐƐ͘ ϯ/ŶƐƚƌƵŵĞŶƚ&ůŝŐŚƚWƌŽĐĞĚƵƌĞƐ;/&WͿĂƌĞƌĞƋƵŝƌĞĚĨŽƌƐĂĨĞĂŶĚĞĨĨŝĐŝĞŶƚĂŝƌĐƌĂĨƚŽƉĞƌĂƚŝŽŶƐ͘dŚĞLJĂƌĞĚĞƐŝŐŶĞĚƚŽ ĨĂĐŝůŝƚĂƚĞĨůŝŐŚƚŽƉĞƌĂƚŝŽŶƐƵŶĚĞƌŝŶƐƚƌƵŵĞŶƚĨůŝŐŚƚĐŽŶƚƌŽů;ŝ͘ĞŶŽŶǀŝƐƵĂůͿĂŶĚŝŶĐůƵĚĞĂƐĞƌŝĞƐŽĨƉƌĞĚĞƚĞƌŵŝŶĞĚ ŵĂŶŽĞƵǀƌĞƐƌĞĨĞƌĞŶĐĞĚďLJĨůŝŐŚƚŝŶƐƚƌƵŵĞŶƚƐ͘ Hillingdon Planning Committee – 16th December 2025 PART 1 – Members, Public & Press used for take-offs) to facilitate aircraft movements from four different runway ends. Runway numbering reflects points of the compass, and a single runway orientated in an east/west direction would be designated runway ‘09’ when in use in an easterly direction and runway ‘27’ when in use in a westerly direction. Heathrow’s two runways are therefore kn own as 27R (right, for the northern runway) and 27L (left, for the souther n runway) when being used in a westerly direction and 09L (northern) and 09R (southern) when used in an easterly direction. 3.33 Aircraft movements are particularly dist urbing immediately after departure and on arrival. The benefit of having two runways and 4 access/departure points is that aircraft can be distributed across the airport to reduce noise impacts. This is known as runw ay alternation and is important in managing aircraft noise for impacted communities. Figure 25: Heathrow Airport runway end designations 3.34 Due to aerodynamic and safety reasons, ai rcraft typically take-off and land into the wind. As the prevailing wind directio n at Heathrow is from a south westerly direction, the Airport is on westerly operations for most of the time, i.e. take-offs are therefore usually towards the west, in the direction of Windsor, whilst arrivals are from the east over central London (known as operating on westerlies). Over the last 20 years (2003 -2022) westerly operations have occurred on average very approximately 70% of the time, meaning the arrivals and departures to the east have occurred around 30% of the time, i.e. 70% of operations are westerly with departures over Windsor and Old Windsor on 09L and 09R. The precise percentage balance between west and ea st can vary year to year as meteorological conditions are never exactly the same. Hillingdon Planning Committee – 16th December 2025 PART 1 – Members, Public & Press Figure 26: Heathrow’s current operation – wind direction 3.35 The Airport’s runways predominantly adopt a segregated mode of operation. Under segregated mode, at any time, local residents at one end of each runway will not be over flown either by arriving or departing aircraft - and will experience what is termed ‘respite’. During westerly op erations, this activity is swapped in the middle of the operating day. Operationally this means (on westerly operations) that from 6:00 am to 3:00pm departing aircraft are directed to one runway and arriving aircraft are directed to the other. The schedules are then alternated or swapped to the other runway from 3:00pm until the final movement, in order to provide predictable periods of respite to residents at the other end of each runway. The pattern is also swapped weekly, as shown below , to give greater variation and respite. Hillingdon Planning Committee – 16th December 2025 PART 1 – Members, Public & Press Figure 27: Direction of arrivals and depart ures on 27R and 27 L during westerly operations (over a two-week period) 3.36 During easterly operations at present there is no alternation, as such there is a full day’s worth of respite over Cranford village and over the relatively sparsely populated Stanwell Moor. Conversely, there is no respite over the relatively densely populated areas of Windsor and Hounslow. There is no change to runway operations at 3pm. Figure 28: Direction of arrivals and depart ures on 09R and 09L during easterly operations 3.37 Alternation schedules are published in advance by Heathrow and allow communities under the flight paths to un derstand when they will benefit from predictable periods of respite. Hillingdon Planning Committee – 16th December 2025 PART 1 – Members, Public & Press 3.38 Alternation has been successfully used for westerly operations for many years, providing communities with predictable reli ef from aircraft arrival and departure noise. However, the Cranford Agreement and the airfield layout which resulted from it has prevented runway altern ation from being implemented while the Airport is on easterly operations since the 1950s. Consequently, when the Airport is on easterly operations, residents living in areas such as Windsor (arrivals) and Hatton (departures) experience noise from arrivals and departures throughout the day without respite. The Cranford Agreement 3.39 The Cranford Agreement was established in 1952 to prevent aircraft departure noise impacts affecting the nearby community of Cranford, i.e. it prevents aircraft taking off on 27R on the northern runway, except in exceptional circumstances. In the 1950s, Heathrow had six runways, arranged in three pairs at different angles in the shape of a hexagram. At that time, Cranford was the nearest and largest population centre to Heathrow’s ru nways. Due to the nature of early jet aircraft, noise from departures was considered to be more disruptive to local communities than noise from arrivals. The Cranford Agreement was therefore an early noise abatement measure which was intended to avoid exposing the nearest population centre to the highest levels of aircraft noise. Figure 29: Heathrow Airport in the 1950s

Subject Eastly Alternation Description Enabling works to allow implementation of full runway alternation during easterly operations Location Heathrow Airport, Hillingdon Reference 41573/APP/2024/2838 1. Introduction to the Review 1.1. The following represents a review of the Noise impacts of the planning application for the works to enable full runway alternation when operating easterly departures. 1.2. The review has been predominantly informed by work completed by Temple noise consultants. 1.3. A summary list of questions, recommendations and clarifications is provided at the end of this document. General 2. LOAEL and SOAEL 2.1. The national policy statement for England (NPSE) sets out the appraisal framework for Local Planning Authorities. This sets out a hierarchy of considerations. • avoid significant adverse impacts on health and quality of life; • mitigate and minimise adverse impacts on health and quality of life; and • where possible, contribute to the improvement of health and quality of life. 2.2. The policy then introduced the following levels to allow for the appropriate assessment of impacts: Appendix 1 • NOEL – No Observed Effect Level • LOAEL – Lowest Observed Adverse Effect Level • SOAEL – Significant Observed Adverse Effect Level 2.3. The NPSE doesn’t specific what the corresponding noise levels noting that these will vary depending on the type of project or source. However, defining these levels is extremely important to determining the impacts of a proposal given the associated policy requirements in relation to mitigation and avoidance of harm. 2.4. The table below identifies the recent positions in relation to Gatwick and Luton, by the applicants and the Examining Authority (ExA) in the case of Gatwick. 2.5. The Secretary of State has been minded to support the position of the Gatwick ExA although also reached a decision on Luton that conflicts. 2.6. As a consequence, and given the significance of the matter, we have taken the decision to seek clarification from the SoS. This has a bearing on our current consideration of this application, noting the position of the Applicant is the same as that for the Applicants, and the SoS decision on Luton expansion. 2.7. The below commentary is therefore without prejudice to the outcome of those considerations. Review of Noise & Vibration Chapter 3. Baseline Conditions (Section 7.4) Introduction 3.1. It is noted that for construction noise, baseline conditions for the period Summer 2025 to Summer 2027 are proposed to align with the currently identified period for construction works. This is considered appropriate. 3.2. For operational noise sources, adoption of a baseline year of 2019 (i.e. pre-COVID) is considered appropriate, as does an assessment year of a proposed commencement of operations in 2028. The operational modelling of 480,000 annual movements to align with the limit imposed by the Terminal 5 planning permission is appropriate. 3.3. Clarification regarding the fleet mix and how the future baseline is calculated is set out below. Method of baseline data collection 3.4. This element has been split into a desk study, and surveys and modelling. 3.5. For the surveys and modelling, a baseline noise measurement survey was carried out at three locations over a one-week period in May 2024 which is considered appropriate for receptors in Longford during the construction period. It is noted that the measurement locations were in the car parks so are slightly closer to the airport than the receptors, but this is not considered to be significant. Study Areas 3.6. Construction Phase: Construction Noise: The proposed construction noise study area is considered appropriate although it is recommended that this be extended until no significant effects are reported. 3.7. Operational Phase: Aircraft Air Noise: The proposed area is considered appropriate although it is recommended this be extended until no significant effects are reported. 3.8. Operational Phase: Aircraft Ground Noise: Given that the proposed study area includes the noise sensitive receptors likely to be exposed to ground noise effects above proposed LOAEL, this is considered appropriate. However, this is subject to further consideration of LOAEL and SOAEL as set out above. 3.9. Operational Phase: Noise Induced Vibration: Focusing on receptors in Longford Village is considered appropriate. Current Baseline 3.10. Current construction baseline: The approach taken to determine the construction baseline noise levels is considered appropriate and agreed. 3.11. Current aircraft ‘air’ noise baseline: The use of a reference year of 2019 (i.e. pre- COVID) is considered acceptable and agreed. 3.12. Current aircraft ‘ground’ noise baseline: The expectation that future ground noise baseline conditions will be lower than the reference year of 2019 is accepted, however the degree of change needs to be reviewed in light of the commentary below relating to assumptions in fleet transition. Future Baseline 3.13. Future Aircraft Air Noise Baseline: The proposed methodology to assess the future aircraft air noise baseline and use of the 480,000 aircraft movement cap is considered appropriate and agreed. 3.14. However, there are concerns over the future baseline of 2028 and how it has been calculated in relation to the current 2019 baseline. 7.4.32 of the Noise Chapter states: Table 7.8 demonstrates a reduction in the area, population and households exposed to aircraft noise for both the summer daytime and summer night- time periods in 2028 without the Proposed Development, compared with conditions in 2019, despite aircraft operations at the airport trending towards larger aircraft types. 3.15. The Table then shows a sizeable difference between the noise exposure from 2019 to 2028. With 7.4.32 providing an explanation of why this change would be realised: The reductions between 2019 and 2028 are predominantly driven by changes in aircraft fleet mix at Heathrow Airport. For example, British Airways retired their Boeing 747-400 aircraft earlier than planned in 2020 due to the impact of the COVID-19 pandemic. Boeing 747-400 aircraft have been replaced with more modern aircraft such as the Boeing 787 Dreamliner and Airbus A350 types which are quieter both on arrival and departure compared to the Boeing 747-400. 3.16. The Chapter then links the expected improvements to a report by the International Civil Aviation Organisation (ICAO) (2019) titled ‘Independent Expert Integrated Technology Goals’ 3.17. The matter of fleet transition was discussed at length during the recent Gatwick Development Consent Order (DCO) examination. Gatwick Airport Limited (GAL) produced an ES Addendum (Updated Central Case - Aircraft Fleet) in May 2024 which stated: The Covid-19 pandemic caused major disruption to the aviation industry globally and those effects are still being felt. The case forecast undertaken in 2021 (2.1.1) 3.18. It included the following diagram to illustrate the impacts on the difference between expectation and reality of fleet progression: 3.19. As a consequence, the noise assessment was updated to reveal that noise contours would not reduce as much as per the original ‘central case’: 3.20. In relation to air noise contours, table 3.1 of the Updated Central Case shows that the 2019 baseline resulted in a 54dB Laeq 16hr contour of 74km2, with the original Central Case showing a reduction to 66.8dB Laeq 16hr. However, the Updated Central Case reflecting updated assumptions regarding fleet transition identifies a more modest 71.8dB Laeq 16hr. 3.21. The information provided in the Noise Chapter (Easterly Alternation) needs to be considered in light of the above. We would look to the Applicant to provide more robust evidence to support their assumptions about the future operating fleet. 3.22. Future Aircraft Ground Baseline: Given the above, commentary on the Future Aircraft Ground Baseline will need to be reviewed as they are inherently linked. 4. Assessment Methodology Construction: Construction Noise 4.1. Noise Metrics: The use of LAeq,T is considered appropriate. It is noted that the time periods proposed for the LAeq,T assessments do not align with the BS 5228-1 time periods so it is recommended that this is amended (e.g. LAeq,5.5hr for night-time should be replaced by LAeq,1hr). This is included as a question/clarification (1). 4.2. Assessment Methodology: Paragraph 7.5.23 infers that the “number of receptors affected” could alter the significance of the effect which requires clarification as to why. This is included as a question/clarification (2). Operational: Aircraft ‘Air’ Noise 4.3. Residential Receptors – Likely Significant Effects: The use of a 1 dB increase (adverse) above the proposed SOAEL is agreed to be conservative approach and is therefore considered acceptable. It is, however, unclear as to what the justification is for the use a 1 dB decrease (beneficial) being significant. This is included as a question/clarification (3). 4.4. While population size (under paragraph 7.5.86) is useful for context, beneficial effects to a large number of people should not be seen to offset adverse effects to others. 4.5. Non-Residential Noise Sensitive Receptors: Where uses include night-time operation (e.g. Hospices, Nursing Homes, Hotels, etc), it is essential that night- time criteria as well as daytime criteria be considered. It is unclear why “commercial non-residential receptors, namely hotels and offices” are considered differently to some other commercial uses e.g. sound recording and broadcast studios so it is recommended that this be discussed. In the case of hotels, it would be appropriate to consider night-time criteria which does not appear to be covered by the current proposals. The values presented in Table 7.23 (Non-residential noise-sensitive receptor types, and absolute ‘lower’ assessment thresholds) require justification as to the internal noise levels that the external noise criteria are aiming to achieve and hence the assumed sound level difference from external to internal for consideration. In the case of “Places of meeting for religious worship” , the “Assumed Ventilation and Cooling Strategy” is stated as “Closed windows” . Since closed windows would not provide ventilation or cooling, further explanation of this approach is required. This is included as a question/clarification (4). 4.6. Parks and Open Spaces – Noise and Amenity: In Table 7.24 Stepped Assessment Methodology for Parks and Open Spaces, under “Impact of Proposed Development” it is recommended that the description of “Intermediate” be revised to “between 25% and 50% of the receptor area” . Under “Assessment” , it is unclear how a “change of 3-5 dB” being considered a likely significant effect differs from “a change of greater than 5 dB” being considered a likely significant effect. This is included as a question/clarification (5). 4.7. Assumptions and Limitations: The stated assumptions are broadly reasonable although further clarification is required in relation to the fleet mix as set out above. Operational: Aircraft ‘Ground’ Noise 4.8. Modelling Methodology: It should be noted that ISO 9613-2 has recently been updated from the 1996 version referenced to a 2024 version which was published on 30 January 2024. While it is acknowledged that modelling work may have commenced prior to this change, it is recommended that, as a minimum, some comparative modelling be undertaken to compare the results from the two versions of the standard. This is included as a question/clarification (6). Operational: Aircraft Noise Induced Vibration 4.9. Concerns have been raised through the consultation about the assessment of noise induced vibration within Longford receptors. Residents have reported impacts with the existing operations on the infrequent occasions the northern runway has been used for easterly departures. 4.10. We would like to understand the role of monitoring/modelling in determining baseline conditions and then how this informs the assessment. Reference to the investigations and measurements previously carried out by Heathrow Airport in a conservatory at the far end of Myrtle Avenue have been outlined but this needs to be explained in more context. This is included as a question/clarification (7). 5. Environmental Measures (Section 7.7) 5.1. Quieter Neighbourhood Support (QNS) Sound Insulation Schemes: Under paragraph 7.7.12, clarification as to whether only one or all three conditions must be met to qualify is required. Under paragraph 7.7.14 it is noted that the scheme boundary will be reviewed at “approximately five-year intervals”; it would be useful if Heathrow could commit to an exact timeframe for these reviews. The full contribution up to a maximum of £34,000 per dwellings requires some further information e.g. what £34,000 currently covers (particularly because it is used as a mitigation to avoid significant effects), whether this value increases over time in line with inflation, and what the scheme covers in terms of replacement of noise insulation measures and regularity. This is included as a question/clarification (8). 5.2. Home Relocation Assistance Scheme (HRAS): As above, further information is required on what £20,000 currently covers, and whether this value increases over time in line with inflation. This is included as a question/clarification (9). Embedded Noise Management Measures 5.3. Construction Phase: Regarding paragraph 7.7.23, consideration of short-term temporary rehousing may be appropriate depending on the predicted construction phase noise levels, so it should not be discounted. This is included as a question/clarification (10). Additional Noise Mitigation Measures 5.4. The financial contributions towards noise insulation described in Table 7.31 should include details of the level of works that £3,000 and up to £12,000 are likely to provide to a recipient for context. This is included as a question/clarification (11). 5.5. Similarly, details of what the “bespoke insulation and ventilation” for schools is likely to include for the cap of £2.5m should be provided for context. This is included as a question/clarification (11). 5.6. Regarding Easterly Alternation Noise Mitigation Package for Noise Induced Vibration, examples of the level of works that £10,000 are likely to provide to a recipient should be included for context. This is included as a question/clarification (11). 5.7. Regarding Easterly Alternation Noise Mitigation Package for Parks and Gardens, it is unclear what the financial contribution of up to £250,000 will mean in terms of “enhancement” and hence additional details should be provided. This is included as a question/clarification (11). 6. Assessment of Potential Effects (Section 7.8) Construction Phase: Construction Noise – Noise Barrier Construction Works – Wright Way (Night-time) 6.1. Table 7.32 “Calculated night-time construction noise levels for Wright Way noise barrier construction works” references façade noise levels in terms of LAeq,5.5hr. In line with BS 5228, it is recommended that the time period of LAeq be referenced to 1hr for night-time works. This is included as a question/clarification (12). 6.2. Given that UAEL is predicted to be exceeded at Receptor 5 for four nights, consideration of an offer of short-term temporary rehousing (i.e. hotel accommodation) should be given in these instances. This is included as a question/clarification (13). Construction Phase: Construction Noise – 09L Airfield Infrastructure Works, Phases 1-3 and ‘On-Alternation’ (Night-time) 6.3. Table 7.34 “Predicted night-time noise levels for Phases 1, 2 and 3 new airfield infrastructure construction works” references façade noise levels in terms of LAeq,5.5hr. In line with BS 5228, it is recommended that the time period of LAeq be referenced to 1hr for night-time works. This is included as a question/clarification (14). 6.4. It is noted that the affected properties have or will be offered sound insulation packages under the QNS scheme. This, and the adoption of Best Practicable Means (BPM) to minimise construction noise are considered appropriate. 6.5. Further construction noise matters will be expected to be dealt with through Section 61 of the Control of Noise Pollution Act. Construction Phase: Construction Noise – 09R/27L Redundant Pavement Removal (Night- time) 6.6. As noted above, it is recommended that the time period of LAeq be referenced to 1hr for night-time works. This is included as a question/clarification (15). Summary of Construction Phase Noise Assessment 6.7. The summary should also include that there are exceedances of the UAEL at Receptor 5 for four nights. This is included as a question/clarification (16). Operational Phase: Aircraft Air Noise – Residential Receptors 6.8. Assessment in Accordance with the Noise Policy Statement for England: Table 7.39 indicates there will be an additional 1,100 people exposed to a level above proposed SOAEL (63 dB LAeq,16hr) because of the development, with 500 over these being above the 69 dB LAeq,16hr threshold for the Home Relocation Assistance Scheme (HRAS). There are also another 1,400 additional people in the 60-63 dB band just below the proposed SOAEL. 6.9. Assessment in Accordance with NPSE – Daytime Exposure: Details of what £34,000 would cover for the QNS in 2024 terms should be sought, along with a commitment for an annual inflationary increase. Regarding paragraphs 7.8.93 and 7.8.94, it is unclear whether reducing noise levels for some people while increasing noise levels for others meets the spirit of the second aim of the NPSE of mitigation and minimising the adverse impacts on health and quality of life between the proposed LOAEL and the proposed SOAEL. In addition, some of the net decrease in this band is due to some people moving to the band above the proposed SOAEL. Some justification around this approach should be provided. This is included as a question/clarification (17). 6.10. Assessment in Accordance with NPSE – Night-time Exposure: As above re: QNS and questioning whether reducing noise levels for some people while increasing noise levels for others meets the spirit of the second aim of the NPSE. Table 7.41 appears to be incorrectly formatted with levels of “55-57” shown as being between (proposed) “LOAEL to SOAEL” and therefore requires correction. This is included as a question/clarification (18). 6.11. The table indicates that an additional 1,700 people will be exposed to levels above proposed SOAEL (55 dB LAeq,8hr) as a result of the development, with 400 of these exposed to level in excess of 63 dB LAeq,8hr (the provisional UAEL for night-time). 6.12. Assessment in Accordance with the NPSE – Conclusion: The above elements are not covered in the conclusion and it is recommended that they should be. Bullet point 3 states that “Although the number of people exposed to air noise above the daytime and night-time proposed SOAEL is forecast to increase due to the Proposed Development in 2028, the increase is much smaller and most of these receptors are already eligible or will become eligible for a funded scheme of insulation under Heathrow’s QNS RIS“. It is recommended that some context be added to this e.g. what is the increase much smaller than. Additionally, demonstrated that the sound insulation scheme will avoid the significant effect is all cases is required. This is included as a question/clarification (19). 6.13. Likely Significant Effects – Daytime: Under Table 7.44, LSE-D07 includes a “very high” number of the population (15,500) who will experience “Exposure between proposed LOAEL and SOAEL and a ‘moderate’ 3 dB – 5.9 dB increase” but will have limited availability to noise insulation funding or, in the case of 12,100, will have no availability to noise insulation funding. Regarding paragraph 7.8.155, there is potential that on some days there will be a need for “having to keep windows closed most of the time” . As such, additional sound insulation provision should be considered for this area. This is included as a question/clarification (20). Operational Phase: Annoyance, Sleep Disturbance and Monetised Outcomes 6.14. Annoyance: The number of people ‘highly annoyed’ is predicted to be lower with development than without, i.e. is beneficial, which is obviously positive. However, it would be useful to understand the number of people who will become ‘highly annoyed’ as a result of the proposed development. This is included as a question/clarification (21). 6.15. Sleep Disturbance: Again, the reduction in the number of people ‘highly sleep disturbed’ is positive but it would be useful to understand the number of people who will become ‘highly sleep disturbed’ as a result of the proposed development. This is included as a question/clarification (22). 6.16. Monetised Outcomes: The TAG analysis effectively assumes ‘symmetry’ so a 1dB beneficial decrease exactly offsets a 1dB adverse increase. It is unclear whether there is evidence for this, particularly in the short to medium term. This is included as a question/clarification (23). Operational Phase: Aircraft Air Noise – Non-Residential Noise Sensitive Receptors 6.17. As noted above, the justification for excluding hotels and offices on the basis that they are commercial enterprises does not make sense when compared with other receptor types such as Theatres, Cinemas, and Sound recording and broadcast studios which would also be commercial enterprises. As such, it is recommended that hotels and offices be included within the assessment. This is included as a question/clarification (24). 6.18. Place of Meeting for Religious Worship: Holy Angels Anglican Church and St Christopher Roman Catholic Church are forecast to experience a ‘moderate’ adverse impact (significant) but no mitigation appears to be being offered to minimise this impact. As noted previously, the assumed ventilation strategy and cooling strategy for these spaces is “Closed Windows” which does not provide ventilation or cooling. This is included as a question/clarification (25). 6.19. Hospitals, Nursing Homes and Hospices: No adverse likely significant effects are reported and hence no comments other than that these should also be assessed for night-time noise as well as daytime. This is included as a question/clarification (26). 6.20. Schools including Registered Nurseries: It is noted that a number of schools will experience levels of up to 60-61 dB LAeq,8hr (alternation period) but will not be eligible for sound insulation. Paragraph 7.8.233 states that “At such levels, internal noise conditions are likely to be below 40 dB LAeq,30min assuming standard façade and roof construction, and a closed window. In other words, no bespoke acoustic insulation measures would be necessary to achieve suitable internal noise conditions for classrooms.” The reference to 40 dB LAeq,30min relates to the Building Bulletin 93 (BB93) “’upper limit’ for indoor ambient noise levels in nursery, primary and secondary school rooms class and teaching rooms for refurbished schools. ” It is unclear why the more relaxed refurbishment criterion has been assumed as opposed to the standard criterion for new schools of 35 dB LAeq,30min. Additionally, it is inappropriate to compare LAeq levels averaged over 8 hours with a criterion averaged over 30 minutes since the LAeq,30min criteria stated in BB93 should assume a worst case 30-minute period over that day. On this basis, further work/justification is required for schools and registered nurseries to demonstrate that appropriate mitigation measures will be adopted. The assumption that windows would be closed requires further consideration; unless a mechanical ventilation system is proposed for schools, windows would need to be opened for both ventilation and cooling. External areas in schools should also be considered. Guidance states “For new schools, 60 dB LAeq,30min should be regarded as an upper limit for external noise at the boundary of external areas used for formal and informal outdoor teaching and recreation “ and “Noise levels in unoccupied playgrounds, playing fields and other outdoor areas should not exceed 55 dB LAeq,30min and there should be at least one area suitable for outdoor teaching activities where noise levels are below 50 dB LAeq,30min“. This is included as a question/clarification (27). 6.21. Summary of Non-Residential Noise Sensitive Receptor Assessment: As noted above, it is recommended that further consideration be given to mitigation (likely to be in the form of noise insulation) to the places of religious worship and schools and registered nurseries where significant adverse effects are predicted but where currently no provision for mitigation is proposed. Operational Phase: Aircraft Air Noise – Parks and Open Spaces – Noise and Amenity 6.22. The approach taken to the assessment of this issue is considered appropriate. 3 parks have been concluded as experiencing potentially significant adverse effects on noise and amenity due to the Proposed Development. The mitigation package of £250k is proposed “towards enhancing these parks in other ways” . It is unclear how this could be used and is unlikely to help mitigate the increased noise levels in these parks. This is included as a question/clarification (28). Operational Phase: Aircraft Ground Noise 6.23. Southwest Quadrant Receptors – Daytime Effects: Paragraph 7.8.301 states “All residential receptors which fall between the daytime proposed LOAEL and SOAEL are forecast to experience a ‘moderate’ increase in daytime ground noise exposure due to the Proposed Development. Clarification as to why this is not reported as a significant effect is required. This is included as a question/clarification (29). Operational Phase Noise Induced Vibration 6.24. It is noted that adverse likely significant effects are concluded for dwellings within 500m of aircraft start of roll but that these dwellings fall within the Heathrow QNS eligibility boundary and would also be eligible for additional funding of up to £10,000 under the Easterly Alternation Noise Mitigation Package for assistance towards the costs of mitigating potential effects (e.g. through reinforcing lightweight floors). 6.25. It is unclear, however, as to whether Littlebrook Nursery, also within 500m of aircraft start of roll, will be eligible for any noise mitigation package. This should be confirmed. This is included as a question/clarification (30). Questions/Clarifications 1. Construction: Construction Noise: Noise Metrics: It is noted that the time periods proposed for the LAeq,T assessments do not align with the BS 5228-1 time periods so it is recommended that this is amended (e.g. LAeq,5.5hr for night-time should be replaced by LAeq,1hr). 2. Construction: Construction Noise: Assessment Methodology: Paragraph 7.5.23 infers that the “number of receptors affected” could alter the significance of the effect which requires clarification as to why. 3. Residential Receptors – Likely Significant Effects: The use of a 1 dB increase (adverse) above the proposed SOAEL is agreed to be conservative approach and is therefore considered acceptable. It is, however, unclear as to what the justification is for the use a 1 dB decrease (beneficial) being significant. 4. Non-Residential Noise Sensitive Receptors: Where uses include night-time operation (e.g. Hospices, Nursing Homes, Hotels, etc), it is essential that night-time criteria as well as daytime criteria be considered. It is unclear why “commercial non-residential receptors, namely hotels and offices” are considered differently to some other commercial uses e.g. sound recording and broadcast studios so it is recommended that this be discussed. In the case of hotels, it would be appropriate to consider night-time criteria which does not appear to be covered by the current proposals. The values presented in Table 7.23 (Non-residential noise-sensitive receptor types, and absolute ‘lower’ assessment thresholds) require justification as to the internal noise levels that the external noise criteria are aiming to achieve and hence the assumed sound level difference from external to internal for consideration. In the case of “Places of meeting for religious worship” , the “Assumed Ventilation and Cooling Strategy” is stated as “Closed windows” . Since closed windows would not provide ventilation or cooling, further explanation of this approach is required. 5. Parks and Open Spaces – Noise and Amenity: In Table 7.24 Stepped Assessment Methodology for Parks and Open Spaces, under “Impact of Proposed Development” it is recommended that the description of “Intermediate” be revised to “between 25% and 50% of the receptor area” . Under “Assessment” , it is unclear how a “change of 3- 5 dB” being considered a likely significant effect differs from “a change of greater than 5 dB” being considered a likely significant effect. 6. Modelling Methodology: It should be noted that ISO 9613-2 has recently been updated from the 1996 version referenced to a 2024 version which was published on 30 January 2024. While it is acknowledged that modelling work may have commenced prior to this change, it is recommended that, as a minimum, some comparative modelling be undertaken to compare the results from the two versions of the standard. 7. Operational: Aircraft Noise Induced Vibration: The approach proposed is considered appropriate. It would however be useful to include a reference to the investigations and measurements previously carried out by Heathrow Airport in a conservatory at the far end of Myrtle Avenue. 8. Quieter Neighbourhood Support (QNS) Sound Insulation Schemes: The full contribution up to a maximum of £34,000 per dwellings requires some further information e.g. what £34,000 currently covers (particularly because it is used as a mitigation to avoid significant effects), whether this value increases over time in line with inflations, and what the scheme covers in terms of replacement of noise insulation measures and regularity. 9. Home Relocation Assistance Scheme (HRAS): As above, further information is required on what £20,000 currently covers, and whether this value increases over time in line with inflation. 10. Construction Phase: Regarding paragraph 7.7.23, consideration of short-term temporary rehousing may be appropriate depending on the predicted construction phase noise levels so it is recommended that it not be discounted. 11. Additional Mitigation Measures: The financial contributions towards noise insulation described in Table 7.31 should include details of the level of works that £3,000 and up to £12,000 are likely to provide to a recipient for context. Similarly, details of what the “bespoke insulation and ventilation” for schools is likely to include for the cap of £2.5m should be provided for context. Regarding Easterly Alternation Noise Mitigation Package for Noise Induced Vibration, examples of the level of works that £10,000 are likely to provide to a recipient should be included for context. Regarding Easterly Alternation Noise Mitigation Package for Parks and Gardens, it is unclear what the financial contribution of up to £250,000 will mean in terms of “enhancement” and hence additional details should be provided. 12. Table 7.32 “Calculated night-time construction noise levels for Wright Way noise barrier construction works” references façade noise levels in terms of LAeq,5.5hr. In line with BS 5228, it is recommended that the time period of LAeq be referenced to 1hr for night-time works. 13. Given that UAEL is predicted to be exceeded at Receptor 5 for four nights, consideration of an offer of short-term temporary rehousing (i.e. hotel accommodation) should be given in these instances. 14. Table 7.34 “Predicted night-time noise levels for Phases 1, 2 and 3 new airfield infrastructure construction works” references façade noise levels in terms of LAeq,5.5hr. In line with BS 5228, it is recommended that the time period of LAeq be referenced to 1hr for night-time works. 15. Construction Phase: Construction Noise – 09R/27L Redundant Pavement Removal (Night-time): As noted above, it is recommended that the time period of LAeq be referenced to 1hr for night-time works. 16. Summary of Construction Phase Noise Assessment: The summary should also include that there are exceedances of the UAEL at Receptor for four nights. 17. Assessment in Accordance with NPSE – Daytime Exposure: Details of what £34,000 would cover for the QNS in 2024 terms should be sought, along with a commitment for an annual inflationary increase. Regarding paragraphs 7.8.93 and 7.8.94, it is unclear whether reducing noise levels for some people while increasing noise levels for others meets the spirit of the second aim of the NPSE of mitigation and minimising the adverse impacts on health and quality of life between the LOAEL and the SOAEL. In addition, some of the net decrease in this band is due to some people moving to the above SOAEL band. Some justification around this approach should be provided. 18. Assessment in Accordance with NPSE – Night-time Exposure: As above re: QNS and questioning whether reducing noise levels for some people while increasing noise levels for others meets the spirit of the second aim of the NPSE. Table 7.41 appears to be incorrectly formatted with levels of “55-57” shown as being between “LOAEL to SOAEL” and therefore requires correction. 19. Assessment in Accordance with the NPSE – Conclusion: The above elements are not covered in the conclusion and it is recommended that they should be. Bullet point 3 states that “Although the number of people exposed to air noise above the daytime and night-time SOAEL is forecast to increase due to the Proposed Development in 2028, the increase is much smaller and most of these receptors are already eligible or will become eligible for a funded scheme of insulation under Heathrow’s QNS RIS“ . It is recommended that some context be added to this e.g. what is the increase much smaller than. Additionally, demonstrated that the sound insulation scheme will avoid the significant effect is all cases is required. 20. Likely Significant Effects – Daytime: Under Table 7.44, LSE-D07 includes a “very high” number of the population (15,500) who will experience “Exposure between proposed LOAEL and SOAEL and a ‘moderate’ 3 dB – 5.9 dB increase” but will have limited availability to noise insulation funding or, in the case of 12,100, will have no availability to noise insulation funding. Regarding paragraph 7.8.155, there is potential that on some days there will be a need for “having to keep windows closed most of the time” . As such, additional sound insulation provision should be considered for this area. 21. Operational Phase: Annoyance, Sleep Disturbance and Monetised Outcomes: Annoyance: The number of people ‘highly annoyed’ is predicted to be lower with development than without, i.e. is beneficial, which is obviously positive. However, it would be useful to understand the number of people who will become ‘highly annoyed’ as a result of the proposed development. 22. Operational Phase: Annoyance, Sleep Disturbance and Monetised Outcomes: Sleep Disturbance: Again, the reduction in the number of people ‘highly sleep disturbed’ is positive but it would be useful to understand the number of people who will become ‘highly sleep disturbed’ as a result of the proposed development. 23. Operational Phase: Annoyance, Sleep Disturbance and Monetised Outcomes: Monetised Outcomes: The TAG analysis effectively assumes ‘symmetry’ so a 1dB beneficial decrease exactly offsets a 1dB adverse increase. It is unclear whether there is evidence for this, particularly in the short to medium term. 24. Operational Phase: Aircraft Air Noise – Non-Residential Noise Sensitive Receptors: As noted above, the justification for excluding hotels and offices on the basis that they are commercial enterprises does not make sense when compared with other receptor types such as Theatres, Cinemas, and Sound recording and broadcast studios which would also be commercial enterprises. As such, it is recommended that hotels and offices be included within the assessment. 25. Operational Phase: Aircraft Air Noise – Non-Residential Noise Sensitive Receptors: Place of Meeting for Religious Worship: Holy Angels Anglican Church and St Christopher Roman Catholic Church are forecast to experience a ‘moderate’ adverse impact (significant) but no mitigation appears to be being offered to minimise this impact. As noted previously, the assumed ventilation strategy and cooling strategy for these spaces is “Closed Windows” which does not provide ventilation or cooling. 26. Operational Phase: Aircraft Air Noise – Non-Residential Noise Sensitive Receptors: Hospitals, Nursing Homes and Hospices: No adverse likely significant effects are reported and hence no comments other than that these should also be assessed for night-time noise as well as daytime. 27. Operational Phase: Aircraft Air Noise – Non-Residential Noise Sensitive Receptors: Schools including Registered Nurseries: It is noted that a number of schools will experience levels of up to 60-61 dB LAeq,8hr (alternation period) but will not be eligible for sound insulation. Paragraph 7.8.233 states that “At such levels, internal noise conditions are likely to be below 40 dB LAeq,30min assuming standard façade and roof construction, and a closed window. In other words, no bespoke acoustic insulation measures would be necessary to achieve suitable internal noise conditions for classrooms.” The reference to 40 dB LAeq,30min relates to the Building Bulletin 93 (BB93) “’upper limit’ for indoor ambient noise levels in nursery, primary and secondary school rooms class and teaching rooms for refurbished schools. ” It is unclear why the more relaxed refurbishment criterion has been assumed as opposed to the standard criterion for new schools of 35 dB LAeq,30min. Additionally, it is inappropriate to compare LAeq levels averaged over 8 hours with a criterion averaged over 30 minutes since the LAeq,30min criteria stated in BB93 should assume a worst case 30-minute period over that day. On this basis, further work/justification is required for schools and registered nurseries to demonstrate that appropriate mitigation measures will be adopted. The assumption that windows would be closed windows also requires further consideration as unless a mechanical ventilation system is proposed for schools, windows would need to be opened for both ventilation and cooling. External areas in schools should also be considered. Guidance states “For new schools, 60 dB LAeq,30min should be regarded as an upper limit for external noise at the boundary of external areas used for formal and informal outdoor teaching and recreation “ and “Noise levels in unoccupied playgrounds, playing fields and other outdoor areas should not exceed 55 dB LAeq,30min and there should be at least one area suitable for outdoor teaching activities where noise levels are below 50 dB LAeq,30min“. 28. Operational Phase: Aircraft Air Noise – Parks and Open Spaces – Noise and Amenity: The mitigation package of £250k is proposed “towards enhancing these parks in other ways” . It is unclear how this could be used and is unlikely to help mitigate the increased noise levels in these parks. 29. Operational Phase: Aircraft Ground Noise: Southwest Quadrant Receptors – Daytime Effects: Paragraph 7.8.301 states “All residential receptors which fall between the daytime LOAEL and SOAEL are forecast to experience a ‘moderate’ increase in daytime ground noise exposure due to the Proposed Development. ” It is questioned whether this should be considered as a significant effect. 30. Operational Phase Noise Induced Vibration: It is unclear whether Littlebrook Nursery, within 500m of aircraft start of roll, will be eligible for any noise mitigation package. This should be confirmed. 31. Clarification around Fleet mix and transition is required with evidence to be produced to demonstrate the current assumptions are accurate.

LBH Noise Response Classification: Internal EASTERLY ALTERNATION INFRASTRUCTURE PROJECT RESPONSE TO LONDON BOROUGH OF HILLINGDON NOISE MITIGATION QUESTIONS: 21 AUGUST 2025 Appendix 2 LBH Noise Response Classification: Internal © Heathrow Airport Limited 2025 1.1 CONTENTS 1. Introduction ................................ ................................ ................................ ......................... 1.2 2. Response to LB Hillingdon Questions ................................ ................................ .............. 2.1 LBH Noise Response Classification: Internal © Heathrow Airport Limited 2025 1.2 1. Introduction 1.1.1 This document provides a response to questions received f rom LB Hillingdon on 15 August 2025. The questions focus on the sufficiency and efficacy of the processes for noise insultation in the context of Heathrow’s application for easterly alternation. 1.1.2 LB Hillingdon raised 7 ‘Questions / Clarifications’ and these are responded to one by one in the table which follows in this document. LBH Noise Response Classification: Internal © Heathrow Airport Limited 2025 2.1 2. Response to LB Hillingdon Questions ID LBH Question/Clarification Heathrow Response 1 Can you provide a range of examples of how the process has worked previously, from application to implementation? I am looking to understand how someone identifies they are eligible, how the application process works, and how the noise insultation reaches the impacted property in accordance with the identified needs. Heathrow’s current noise insulation scheme is provided through the Quieter Neighbo urhood Scheme or QNS. Properties are eligible for the QNS scheme if they are located within the single composite boundary based on a number of noise metrics and current UK noise policy (Significant Observed Adverse Effect Level (SOAEL) for day and night and based on scheduled operations before 06:00, the Sound Exposure Level (SEL) footprint of the noisiest aircraft and the calculated probability of >1 additional awakening. Information) . The eligibility criteria were endorsed by government in Heathrow’s Noise Action Plan and is based on up-to-date noise modelling to ensure the boundary remains reflective of changes to noise exposure over time. We provide information regarding the scheme on our website (https://www.heathrow.com/company/local- community/noise/what-you-can-do/quieter-neighbourhood-support/residential-insulation). This is provided in multiple languages to ensure the information is easily accessible to as many residents as possible. The website also includes a postcode checker (https://www.heathrow.com/company/local-community/noise/what-you-can- do/quieter-neighbourhood-support/postcode-checker) and map of active eligible zones and indictive timescales so that residents can determine if they are eligible. Residents are able to access this information online which is updated periodically. Residents are also welcome to contact communityschemes@heathrow.com or call 0800 344 844 for information regarding the scheme. In addition to providing information online, we contact residents as we open each phase of the scheme to invite them to register when their area becomes active. This contact is first done via letter drop. Following this, we proactively promote the scheme through door knocking, word of mouth, on site branding, and outreach to local leaders to encourage sign-up to the scheme. We are also planning a community engagement van and increased local advertising to improve take-up of the scheme. We hope that this proactive approach will enable us to achieve our target set out in the Noise Action Plan of at least 80% of eligible properties taking up the scheme. Given the large number of properties that fall within the composite noise contour boundary, Heathrow is inviting properties to register for the scheme in phases, to ensure efficiency in the delivery of noise insulation. The roll-out programme of eligible areas has been determined based on prioritising insulating areas most effected by aircraft noise and considering how the delivery supply chain can most efficiently undertake works on groups of properties in areas rather than reacting to registrations ad hoc. The roll out program has been agreed with the independent LBH Noise Response Classification: Internal © Heathrow Airport Limited 2025 2.2 ID LBH Question/Clarification Heathrow Response Prioritisation Panel (see response to question 7), and it was identified to prioritise Longford as the area to conduct the first pilot implementation of the scheme in 2024. This phased approached to implementation of the scheme is defined by the QNS Master Programme Delivery Model. QNS master programme follows a tiered and sequenced approach that ensures clarity, efficiency, and responsiveness at every stage of delivery: 1. Strategic Planning - This begins with a master plan outlining delivery logic, sequencing, and geographic priorities. Phases are defined by eligibility, noise contour modelling, and Prioritisation Panel endorsement. Each phase is linked to timelines and engagement strategies via Customer Relationship Management (CRM) tools like Salesforce. 2. Zone-Level Planning - Phases are divided into zones based on geographic and operational traits. Planning includes survey schedules, access guides, and community engagement. The output of this delivery stage is a Zone Analysis Report and Archetyping Validation Report. 3. Tranche-Level Delivery - Zones are broken into tranches for targeted delivery. Delivery activities for each tranche include property surveys to inform delivery, issuing Property Work Proposals (PWPs), confirming installation times, and managing access. 4. Household Engagement - Residents receive personalised communications, appointment confirmations, and follow-ups. Special cases and unresolved issues are escalated to the Prioritisation Panel (see Q7 response). Benefits of the Phased-Zone-Tranche based delivery model are summarised in the table below: Benefit Area Key Advantages Predictability Clear timelines and aligned communications reduce confusion. Localised Engagement Tailored messaging and events; feedback informs strategy. CRM-Driven Efficiency Salesforce enables automation, segmentation, and real-time reporting. Flexibility Prioritisation Panel adapts plans; residents can opt for upgrades. Resident Experience PWPs clarify scope; satisfaction surveys and support build trust. LBH Noise Response Classification: Internal © Heathrow Airport Limited 2025 2.3 ID LBH Question/Clarification Heathrow Response For delivery of the Easterly Alternation mitigation, Heathrow will use reasonable endeavours to ensure that where offers are accepted, all agreed works are completed prior to the commencement of easterly alternation operations. The programming of the QNS delivery will be updated to account for this. As an example of how the process works in practice, below is an overview of the steps taken on the QNS scheme for delivery of noise insulation to a resident, from application to implementation. As part of the QNS delivery process, it should be highlighted there are two sides of delivery management of the scheme that report into Heathrow: • Delivery Partner - Manages residential delivery, community buildings, marketing, adobe buildings, and vortex and roofing. • Service Integrator – Manages scheme helpdesk, surveying & auditing, and professional services. Process implementation overview: Step 1: The Heathrow Helpdesk writes to eligible customers encouraging them to sign up to the Residential Insulation Scheme (RIS). This is followed up by door knocking and other methods to promote uptake of the scheme. . Step 2: Customers register their interest with the Heathrow Helpdesk Step 3: Our Service Integrator acoustics team book a noise survey with the customer. Step 4: Once the noise survey has been carried out the Service Integrator produces a statement of needs for the customer’s property and allocates a case number for the works. Step 5: The Service Integrator issue the statement of needs to the insulation scheme Delivery Partner who are responsible for delivering the insulation works. Step 6: Delivery Partner receives the statement of needs via Salesforce. Step 7: Upon receiving the statement of needs the Delivery Partner calls the customer to arrange a pre-works survey. They will also fill out the resident profile form at this stage so that they understand the customer and their needs prior to the pre survey taking place. LBH Noise Response Classification: Internal © Heathrow Airport Limited 2025 2.4 ID LBH Question/Clarification Heathrow Response Step 8: Once the appointment has been confirmed over the phone, the customer will receive an email confirming the agreed date, the sub-contractor visiting, and time slot in which the pre works survey will take place. We will only send a letter if the customer asks us for one instead of an email. Step 9: The contractor and site team attend the resident’s home to carry out the pre-works survey. Step 10: Once the survey for works has been carried out, the contractor will share their findings and produce a property noise proposal. This proposal will include information on the windows, doors, ventilation, and insulation requirements including detailed measurements. The proposal will identify the specification to achieve the acoustic aims of the scheme. The RIS aims to achieve the recommendations of BS8233:2014 and the WHO guidelines for internal ambient noise levels. Heathrow accept that this target may not be able to be achieved in certain circumstances due to the limitations of the existing building fabric/structure . Step 11: Following production of a property noise proposal, a task order for the work is produced . This task order will include any amendments to scope or spec by resident. The resident is able to choose the type of ventilation product they want to have installed, and subject to the existing design of the windows and doors they will also have a choice from a standard product range. It is also within the resident’s gift to omit certain elements of the package being offered (e.g. not go ahead with the ceiling over boarding). In instances where a resident chooses not to include a certain element identified in the property noise proposal, Heathrow and our delivery team, make sure to explain that this could reduce the intended insulation performance of the original package being offered. Upon receipt of the task order, the Service Integrator team will review the scope/spec and cost. If the Service Integrator is happy with the costs and proposal, they will sign it off. In the event they are not happy with it they will seek to amend or approve. If the costs exceed the cost cap, the work order will be referred to Heathrow and the Prioritisation Panel, along with the associated costs and an explanation of why the costs have exceeded the cap. Step 12: Once the task order is approved, the Delivery Partner will contact the resident in order to book a date when the works can go ahead. Once the appointment has been confirmed over the phone , the Delivery Partner will send the customer an email confirming the agreed date, sub-contractor visiting, and time slot in which the works will take place. Step 13: The works take place at the resident’s property. Step 14: The works are completed at the resident’s property. LBH Noise Response Classification: Internal © Heathrow Airport Limited 2025 2.5 ID LBH Question/Clarification Heathrow Response Step 15: Once all the works are carried out at the resident’s property the Delivery Partner will issue to the customer a property handover pack. This will include all works photographs as detailed in the ‘Construction Phase Quality Assurance Photograph Requirements’, Contractor works completion report, Detailed property tracker outlining variations to works. Step 16: An audit is undertaken by Heathrow’s appointed property consultant (an RICS registered practice), who are part of the Service Integrator team, in order to confirm if the work is satisfactory or not. If there are snagging issues or defects, then the Delivery Partner will rectify these issues booking in with the customer an appointment to carry out these works. If there are no issues, then the work is signed off as complete. Case Studies The following are some case studies of properties that have been through the QNS delivery process. Property A Property A - Block of 53 Flats (UB7) – Received new acoustically rated aluminium windows and ventilation. Total cost of works: Approx £6,500 per apartment. Process duration (Step 3-16): 5 Months Step 1: Invitation to register issued (February 2024). Step 2: Door knocking exercise undertaken x 3 at (2-month intervals) . Step 3: Resident register to participate in the scheme (July 2024). Step 4: Noise survey booked. (July 2024). Step 5: Noise Survey Undertaken (July 2024). Step 6: Property noise proposal drafted (July 2024). Step 7: Property noise proposal issued to the resident. (July 2024). Step 8: Contractor undertakes asbestos survey (July 2024). Step 9: Contractor carries out survey of the property (July 2024). LBH Noise Response Classification: Internal © Heathrow Airport Limited 2025 2.6 ID LBH Question/Clarification Heathrow Response Step 10: Contractor drafts property works proposal. (July 2024). Step 11: Resident signed document (August 2024). Step 12: Manufacturing Period and works booking (August 2024). Step 13: Works start on site. (August 2024). Step 14: Works complete. (October 2024). Step 15: Snagging and Final Inspection (October 2024). Step 16: Provision of Property Handover Pack (November 2024). Property B Property B – 3 Bed Semi Detached (UB7) – Received new acoustically rated PVCu windows, ventilation, and loft insulation. Total cost of works: Approx £17,500. Process duration (Step 3-16): 4 Months Step 1: Invitation to register issued (February 2024). Step 2: Door knocking exercise undertaken – N/A Step 3: Resident register to participate in the scheme (February 2024). Step 4: Noise survey booked. (February 2024). Step 5: Noise Survey Undertaken (March 2024). Step 6: Property noise proposal drafted (March 2024). Step 7: Property noise proposal issued to the resident. (March 2024). Step 8: Contractor undertakes asbestos survey (March 2024). LBH Noise Response Classification: Internal © Heathrow Airport Limited 2025 2.7 ID LBH Question/Clarification Heathrow Response Step 9: Contractor carries out survey of the property (March 2024). Step 10: Contractor drafts property works proposal. (March 2024). Step 11: Resident signed document (April 2024). Step 12: Manufacturing Period and works booking (April 2024). Step 13: Works start on site. (April 2024). Step 14: Works complete. (April 2024). Step 15: Snagging and Final Inspection (May 2024). Step 16: Provision of Property Handover Pack (May 2024). Property C Property C – 2 Bed Apartment in Conservation Area (TW7) – Received new acoustically rated Timber windows, ventilation, and loft insulation. Total cost of works: Approx £35,000. Process duration (Step 3-16): 10 Months Step 1: Invitation to register issued (June 2023). Step 2: Door knocking exercise undertaken – N/A Step 3: Resident register to participate in the scheme (June 2023). Step 4: Noise survey booked. (July 2023). Step 5: Noise Survey Undertaken, identified that local authority consent is required (July 2023). Step 6: Property noise proposal drafted (July 2023). Step 7: Property noise proposal issued to the resident. (July 2023). LBH Noise Response Classification: Internal © Heathrow Airport Limited 2025 2.8 ID LBH Question/Clarification Heathrow Response Heathrow support resident to obtain consent. (July- November 2023) Step 8: Contractor undertakes asbestos survey (November 2023). Step 9: Contractor carries out survey of the property (November 2023). Step 10: Contractor drafts property works proposal. (November 2023). Step 11: Resident signed document (December 2023). Step 12: Manufacturing Period (12 weeks) and works booking (December 2023 – February 2024). Step 13: Works start on site. (March 2024). Step 14: Works complete. (March 2024). Step 15: Snagging and Final Inspection (March 2024). Step 16: Provision of Property Handover Pack (April 2024). 2 Can you provide examples of what the differing funding packages practically secure - i.e. what does £3k achieve with regards to noise insultation? I am after the specifications and details of the specific work. The financial assistance towards noise insulation has been offered by Heathrow for residential dwellings which are forecast to experience increases in noise (>3 dB) leaving them exposed to at least 54 dB LAeq,16hr due to Easterly Alternation. Fully funded noise insulation packages are not offered at levels of exposure outside of the QNS eligibility criteria. As noise exposure level goes down below the criteria defined by the QNS eligibility, the proportion of people likely to be annoyed or sleep disturbed reduces. We do however recognise that a proportion of the population exposed to levels between 54 – 60 dB and 60 – 63 dB LAeq,16hr may experience an effect and therefore we offer a contribution towards those residents purchasing noise insulation if they choose to do so. These funding packages are intended to be used by residents as a contribution towards the total cost of insulation in line with government policy, however if a resident wanted to explore what the sum or either £3,000 or £12,000 could purchase without any additional financial input from themselves we have set out the examples provided in our previous response in more detail below: LBH Noise Response Classification: Internal © Heathrow Airport Limited 2025 2.9 ID LBH Question/Clarification Heathrow Response With £3,000: We anticipate that properties between 54-60 dB LAeq,16hr should be able to meet BS 8233 internal average ambient noise levels in habitable rooms with standard glazing (assumes existing glass retained and is double- glazed unit), loft insulation and an enhanced Siegenia vent or PIV. Total estimated cost of PIV and loft Insulation: - Contractor surveys – £200 - Ventilation Product - £1300 - Loft Insulation including hatch and perimeter seal (50 SQM Average Property size) – £1500 Total £3,000 EX VAT We are confident that the measures proposed (namely new ventilation and loft insulation) will meet the required internal ambient noise levels. We have supporting evidence (contractor final accounts to suggest that the £3k figure can provide the necessary measures outlined). With £12,000: We anticipate that properties 60-63dB will require windows to be replaced to meet 8233 internal average ambient noise levels, as well as loft insulation and a Siegenia vent or PIV. - Contractor surveys – £500 - Ventilation Product - £1300 - Bathroom / Kitchen Ventilation - £1500 - Loft Insulation (50 SQM Average Property size) - £1500 - Secondary Glazing – (8 No. secondary glazing units between 3 & 4 Sqm) - £7200 Total £12,000 EX VAT As per the above, we are confident that the measures proposed (namely secondary glazing, new ventilation and loft insulation) will meet the required internal ambient noise levels. Again, we have supporting evidence (contractor final accounts to suggest that the £12k figure can provide the necessary measures outlined). 3 Does Heathrow Airport Ltd track the eligible properties, Heathrow keeps track of a number of metrics and data points for the QNS scheme including: - Eligible properties (registered and not registered for the scheme) LBH Noise Response Classification: Internal © Heathrow Airport Limited 2025 2.10 ID LBH Question/Clarification Heathrow Response and can this information be shared? - Ineligible properties - Surveys completed (noise and building) - Property information packs drafted/issued - Validation surveys undertaken - Properties on hold (this could be for a number of reasons that require further investigation) - Works approved - Works underway - Works completed As part of delivery of the Easterly Alternation mitigation packages, this will be included in the data we track for the broader QNS scheme. We can provide LBH with a copy of the annual report which we will produce with the Prioritisation Panel and CISHA for the scheme as a whole. This will include data specific to the additional Easterly Alternation mitigation offer. 4 Are post implementation checks undertaken to determine the efficacy of the works? As part of the QNS program, an ongoing quality assurance process is undertaken by the Service Integrator to ensure the insulation has been installed correctly and all works have been finished to a good standard. This process is set out under the three stages below: Stage 1 Heathrow’s appointed property consultant (an RICS registered practice) who is part of the Service Integrator team will carry out weekly interim inspection of properties undergoing insulation works during the construction phase to ensure that the levels of quality outlined in the specification are being complied with. Upon completion of the inspection the consultant provides an inspection report and tracks the progress of the property until the works are completed. Stage 2 Upon completion of the work, the appointed property consultant carries out a final inspection to confirm that the works meet Heathrow’s requirements as outlined within the performance specification document for the project. Upon completion of the inspection, the consultant produces a final inspection report which accurately records the works completed at the property along with any snagging works outstanding. This report is shared with Heathrow LBH Noise Response Classification: Internal © Heathrow Airport Limited 2025 2.11 ID LBH Question/Clarification Heathrow Response and the QNS Delivery Partner. All snagging items are discussed verbally with the resident directly, so they are aware of outstanding works. Stage 3 The appointed consultant manages the snagging process ensuring that the contractor has completed all outstanding works identified at the time of the final inspection. A follow up inspection will then usually be undertaken to confirm that these works have been completed. The requirement for a close out inspection is dependent upon the nature and quantity of snagging items identified. In certain situations, snagging items may be closed out by reviewing photographs against the snagging list. This minimises disruption to the resident which may be caused by the undertaking of an additional inspection. Post works noise surveys are also undertaken on a representative sample of properties (10%) to confirm that the measures installed provide the required level of performance. In addition, our Service Integrator Team use their professional experience to ensure that the works are completed to a high standard so that the performance parameters are achieved. By following a detailed quality assurance process the QNS scheme is able to ensure that installation of materials and products meets manufacturers’ requirements and building regulations, ensuring that the performance of the insulation meets the product specification and property needs. Residents who choose to participate are also invited to take a satisfaction survey of the works undertaken (see response to Q6 for more information). 5 What support is provided to a recipient in the event that there are complications? - i.e. more money is required due to unforeseen technical problems. Where an issue or complication arises, there are a number of support options available to the resident depending on the nature of the issue. First and foremost, the nature of the issue is raised with the resident so that they are aware of it and can understand the implications it may have on timescales and delivery of the insulation package. For properties that meet the QNS eligibility criteria for insulation, where an unforeseen technical issue arises, HAL and our Delivery Partner would seek to remedy the issue in order to minimise delaying installation of the noise insulation for the resident. This is subject to the additional cost of the remedial works not exceeding the scheme cost cap of £34,000. Where the cost of additional unforeseen works exceeds the scheme cost cap, or the property is only eligible for one of the financial contribution offers, these cases would need to be considered on a case-by- case basis, considering the origin position and the cause of the complications. An example that we have already experience as part of the QNS scheme is properties not having the appropriate lintel construction in order to install windows and doors. Where this was discovered, remedial works to construct LBH Noise Response Classification: Internal © Heathrow Airport Limited 2025 2.12 ID LBH Question/Clarification Heathrow Response the appropriate lintels into the properties was undertaken (funded under the QNS delivery program) so that the insulation packages could be installed. There may be instances where the issue / complication is more complex, or results in the cost of additional works exceeding the agreed scheme cost cap. These cases would be referred to the Prioritisation Panel who would review the case and make a recommendation to Heathrow on how to proceed. This could include them recommending that HAL cover the additional cost. Further information on the Prioritisation Panel is provided in the response to Question 7. In order to deliver the scheme as efficiently as possible. the QNS operates a proactive approach to risk identification and mitigation, what this means is: 1. Survey-Led Risk Profiling - The QNS process begins with a structured sequence of surveys; noise survey and pre-works survey to assess asbestos, lintels, cavity space, and structural integrity. These surveys are designed to flag risks early, such as asbestos or structural issues, and trigger predefined mitigation pathways. 2. Resident Profiling & Vulnerability Mapping - During the pre-works survey, a resident profile form is completed to understand individual needs, vulnerabilities, and preferences. This enables tailored support and flags cases requiring additional care. 3. Monitoring & Evaluation Framework - Resident feedback is collected via surveys and community meetings. A monitoring framework tracks emerging risks and service gaps. Adjustments are made monthly based on stakeholder input. In addition to the proactive approach to risk identification and mitigation, the following reactive support and escalation pathways exist: 1. Complaint Management & Case Ownership - When issues arise, such as poor service or unmet expectations: a. Complaints are logged and categorised by primary issue. b. Each live complaint is assigned a case owner. c. Resolution is prioritised by severity and age of complaint. LBH Noise Response Classification: Internal © Heathrow Airport Limited 2025 2.13 ID LBH Question/Clarification Heathrow Response d. A dedicated team, including additional CLOs (Customer Liaison Officers), is mobilised to re - establish contact and provide updates. 2. Cross-Partner Coordination - Escalations involving the Delivery Partner or Service Integrator are managed through weekly meetings and direct engagement. Established governance groups serve as forums to flag, escalate and triage emerging issues Legal and commercial complexities (e.g. TUPE, liability) are escalated to contract managers and legal advisors. Benefits of the undertaking a proactive approach to risk management include: 1. Early Risk Detection: Multi-layered surveys catch issues before works begin. 2. Tailored Resident Support: Vulnerability mapping ensures no one is left behind. 3. Structured Escalation: Case ownership and weekly triage meetings drive accountability. 4. Cross-Functional Collaboration: Heathrow, Kier, and TFT work in lockstep to resolve issues. 5. Continuous Improvement: Feedback loops and audits refine processes over time. 6 Are there feedback surveys undertaken about the satisfaction of the process? To help assess the effectiveness of our home insulation schemes, we carry out short surveys with participating residents to measure their overall satisfaction. These surveys are an important part of our commitment to continuous improvement, ensuring that the schemes deliver real and lasting benefits to households. Residents are interviewed at three stages of each scheme: • Quieter Nights Scheme (QNSS): noise assessment, supplier visit, and completion of works. • Vortex Scheme: initial visit, remedial repair, and completion of works. By engaging with residents at different stages of the process, we are able to identify and resolve any issues in real time. Each survey includes around 10 questions, covering topics such as how residents first accessed the scheme, the extent to which aircraft noise affects their quality of life, their experience of the works process, and whether their quality of life has improved post-installation, including their perceptions of Heathrow as a neighbour. LBH Noise Response Classification: Internal © Heathrow Airport Limited 2025 2.14 ID LBH Question/Clarification Heathrow Response We take this feedback seriously. It not only helps us improve the experience for current residents but also informs how we design and deliver future schemes, ensuring that they continue to meet the needs of the communities we serve. We expect to include a summary of this feedback within the scheme annual report. 7 Is there a complaints process, independent oversight, dispute resolution process? Complaints and special cases can be escalated to the Prioritisation Panel. The Prioritisation Panel was established as part of Heathrow’s delivery model for the Quieter Neighbour Support programme, with the remit of: - Within the financial scope set, and options provided by Heathrow, to provide advice and guidance on the prioritisation of works under the Quieter Neighbour Support programme, - To establish a coherent approach and rationale for prioritisation, and, - To determine outcomes in special cases or escalated disputes in a consistent manner. Its membership comprises a small number of representatives from: - CISHA (Panel chair) - HACAN - HSPG - Airline Operators Committee - health effects expert (University of London) - Heathrow Where a resident believes they have a special case, or they wish to escalate a complaint/dispute, this will be taken to the Prioritisation Panel who will review each case and make a recommendation to Heathrow on how to proceed. The panel meets once a quarter to discuss scheme implementation progress and review special cases. Where a particular dispute or case requires more urgent attention by the panel, these can be reviewed on an ad hoc basis. LBH Noise Response Classification: Internal © Heathrow Airport Limited 2025 2.15 ID LBH Question/Clarification Heathrow Response Examples of disputes and cases that the Panel has dealt with to date include: - Consideration of medical conditions which makes the resident more sensitive to noise exposure. In such cases the panel will undertake consideration of the noise exposure level of the property and confirmation of medical condition from a healthcare professional. - Cost of insulating a property exceeding the set cost cap for the scheme. - Property licensing/classification irregularities (e.g., a property being operated as an HMO without the correct license in place). In 2024 the implementation of the special cases process began. That year, eight cases were referred to the Panel for review and made recommendations to Heathrow on how to proceed. These cases included medical conditions (for which the Panel requested proof to support the consideration) and cost cap exceedances. All cases were recommended by the Panel for works following receipt of the additional information requested. In 2025 (YTD) there have been 19 cases referred to the panel. Fourteen of the cases were due to cost cap exceedances. The works for these were recommended for works by the Panel subject to one property having a scope reduction due to the significant exceedance of the cost cap. Three of the cases in 2025 were based on medical conditions, all of which were recommended by the panel for works. One property was a residential property converted to a care home (classes as commercial building) and was recommended for works by the Panel. Finally, property was thought to be an unlawful HMO. The Panel requested further information to establish key facts. Engagement with the landlord was undertaken to recommend that the appropriate licenses were obtained. This is underway and insulation works will be able to be undertaken. In all instances, Heathrow has accepted the Panel’s recommendations and has proceeded with the work where that is the Panel’s position.

LBH Noise Response Classification: Public NATS Internal EASTERLY ALTERNATION INFRASTRUCTURE PROJECT RESPONSE TO LONDON BOROUGH OF HILLINGDON ON NOISE MATTERS, JULY 2025 Appendix 3 LBH Noise Response Classification: Public © Heathrow Airport Limited 2023 ii LBH Noise Response Classification: Public © Heathrow Airport Limited 2023 iii CONTENTS 1. Introduction ................................ ................................ ................................ ......................... 1.1 2. Response to LB Hilligdon review ................................ ................................ ...................... 2.1 Appendices Appendix A Heathrow Vibration Report LBH Noise Response Classification : Public © Heathrow Airport Limited 2023 1.1 1. Introduction 1.1.1 This document provides a response to questions received from LB Hillingdon on 24 June 2025 in a document which formed a review of the Noise impacts of the planni ng application for works to enable full runway alternation when operating easterly departures. In particular, the document provided a review of the Noise chapter and appendices provided as part of the Environmental Statement accompanying Heathrow’s application for those works, which was submitted in October 2024. 1.1.2 The Borough Council’s review raised 31 ‘Questions / Clarifications’ and these are responded to one by one in the table set out in Section 2. LBH Noise Response Classification : Public © Heathrow Airport Limited 2023 2.1 2. Response to LB Hillingdon review ID LBH Question/Clarification Heathrow Response 1 Construction: Construction Noise: Noise Metrics: It is noted that the time periods proposed for the LAeq,T assessments do not align with the BS 5228-1 time periods so it is recommended that this is amended (e.g. LAeq,5.5hr for night-time should be replaced by LAeq,1hr). The night-time assessment period for identifying potential significant effects in the ‘ABC method’ of BS5228 -11 is 23:00 – 07:00 (8 hours) as shown in Section E.3.2 / Table E.1 and reproduced in Table 7.12 of the ES. This assessment methodology has been supplemented with 5.5 hour assessment period of 23:00 – 04:30 to reflect the period when night-time construction works are forecast to occur based on the indicative construction programme and working methods. This is also the period of the night during which there is reduced aircraft activity and hence the use of a reduced 5.5 hour assessment period is considered a conservative approach. Section E.4 / Table E.2 of BS5228-1 includes a 1 hour averaging period, however this is in the context of “thresholds used to determine the eligibility for noise insulation and temporary rehousing ”, rather than in the context of identifying significant effects. At the planning stage the level of detail in working methods was not, and is still not, sufficiently detailed to allow for 1-hour assessments. Heathrow propose that construction noise is managed through a Section 61 process overseen by London Borough of Hillingdon (LBH) under the Control of Pollution Act 1974, which will allow a more granular assessment of any necessary mitigation to be developed by agreement at that time . 2 Construction: Construction Noise: Assessment Methodology: Paragraph 7.5.23 infers that the “number of receptors affected” could alter the significance of the effect which requires clarification as to why. As noted in paragraph 7.5.23 of the ES, where likely significant effects are identified, the number of receptors affected is “discussed to provide context to the effects”. The number of receptors affected provides important context to the scale of the identified effect. It has not been used to alter the reported significance of the effect. 1 British Standards Institution (2014). BS 5228-1:2009+A1:2014 Code of practice for noise and vibration control on construction and open sites: Part 1 – Noise. London: BSI. LBH Noise Response Classification : Public © Heathrow Airport Limited 2023 2.2 ID LBH Question/Clarification Heathrow Response 3 Residential Receptors – Likely Significant Effects: The use of a 1 dB increase (adverse) above the proposed SOAEL is agreed to be conservative approach and is therefore considered acceptable. It is, however, unclear as to what the justification is for the use a 1 dB decrease (beneficial) being significant. Minor changes in noise (1.0 - 1.9dB) above the SOAEL are treated as likely significant effects for both increases and decreases. The noise exposure hierarchy table in Planning Practice Guidance Noise (PPG -N2) notes that between the LOAEL and SOAEL noise exposure is “present and intrusive”, “causes small changes in behaviour” and “affects the acoustic character of the area such that there is a small actual or perceived change in the quality of life”. PPG-N notes that noise exposure above the SOAEL is “present and disruptive”, “causes a material change in behaviour” and notes “Quality of life diminished due to change in acoustic character of the area.” This increased effect on people’s health and quality of life from noise above SOAEL means that smaller noise changes above SOAEL (increases and decreases) can lead to a likely significant effect. As noted in the ES, this is consistent with PPG-N which states "In cases where existing noise sensitive locations already experience high noise levels, a development that is expected to cause even a small increase in the overall noise level may result in a significant adverse effect occurring even though little to no change in behaviour would be likely to occur." Whilst this statement specifically mentions noise increases, the context of the statement and the noise exposure hierarchy table described above makes clear that the same would be true of noise decreases. This approach is also consistent with other noise assessment methodologies such as the Design Manual for Roads and Bridges (DMRB3) which notes that noise changes (increases or decreases) of 1.0dB or more would result in a likely significant effect. Heathrow is confident that the assessment of effects that is documented within the ES complies with the requirements of the EIA Regulations and provides sufficient information for LBH to reach a reasoned conclusion on the likely significant effects of the proposed development on the environment and to decide the application . 2 Ministry of Housing, Communities and Local Government, Ministry of Housing, Communities & Local Government (2018 to 2021) and Department for Levelling Up, Housing and Communities (2019). Noise. [online] Available at: https://www.gov.uk/guidance/noise --2 (Accessed June 2025) 3 Standards for Highways (2020). Design Manual for Roads and Bridges. LA 111 - Noise and Vibration. [online] Available at: https://www.standardsforhighways.co.uk/search/cc8cfcf7-c235-4052-8d32-d5398796b364 (Accessed June 2025). LBH Noise Response Classification : Public © Heathrow Airport Limited 2023 2.3 ID LBH Question/Clarification Heathrow Response 4 Non-Residential Noise Sensitive Receptors: Where uses include night- time operation (e.g. Hospices, Nursing Homes, Hotels, etc), it is essential that night-time criteria as well as daytime criteria be considered. It is unclear why “commercial non- residential receptors, namely hotels and offices” are considered differently to some other commercial uses e.g. sound recording and broadcast studios so it is recommended that this be discussed. In the case of hotels, it would be appropriate to consider night-time criteria which does not appear to be covered by the current proposals. The values presented in Table 7.23 (Non-residential noise- sensitive receptor types, and absolute ‘lower’ Night-time assessment of hospitals, hospices, nursing homes and hotels A night-time assessment of noise sensitive non-residential receptors that include night-time operation (hospitals, hospices, nursing homes and hotels) has been undertaken within the ES and reported where relevant. It is summarised below. The construction noise assessment provided within the ES considers night-time effects at hospitals, hospices, nursing homes and hotels using the methodology described in paragraphs 7.5.19 to 7.5.23. No night -time significant effects are identified other than a night-time likely significant effect during the 09L airfield works for the Thistle London Heathrow Terminal 5. This is included in the summary of effects in paragraph 7.8.50 and Table 7.52. For air and ground noise, the assessment methodology includes a night-time assessment for hospitals, hospices, nursing homes and hotels4. For ground noise, it is reported that no likely significant effects are concluded for these receptors during the night -time (see paragraphs 7.8.279, 7.8.288, 7.8.298 and 7.8.306). For air noise, paragraph 7.5.99 notes that whilst an assessment of night-time effects for hospitals, hospices, nursing homes and hotels was undertaken, the reporting focusses on daytime effects as it is during daytime periods that changes in aircraft noise due to the Proposed Development main occur. In fact, nowhere is there a receptor that experiences a night-time significant effect that is not also subject to significant effects during the day. “The assessment has focussed on changes in daytime noise exposure as it is during the day that the Proposed Development has the greatest impact on the distribution of aircraft noise around the Airport. However, the daytime and night-time ‘lower’ assessment thresholds from Table 7.23 have both been applied in identifying receptors.” The assessment methodology for non-residential receptors in Section 7.5 notes that night-time likely significant effects are initially identified for receptors that both exceed the lower assessment thresholds in Table 7.23 (and Section 9 of Appendix 7.5 for hotels) of the ES and experience at least a ‘moderate’ noise change of 3dB or greater. 4 Table 7.23 includes night-time screening criteria of 50dBLAeq,8h for “Hospitals and other healthcare settings”. Footnote 133 to this table notes that this includes CM03HI (hospital/hospice) and RI01 (nursing homes). The night-time lower assessment thresholds for hotels of 45dBL Aeq,8h is specified in Section 9 (Assessment of Hotels and Offices Uses) of Appendix 7.5 of the ES. LBH Noise Response Classification : Public © Heathrow Airport Limited 2023 2.4 ID LBH Question/Clarification Heathrow Response assessment thresholds) require justification as to the internal noise levels that the external noise criteria are aiming to achieve and hence the assumed sound level difference from external to internal for consideration. In the case of “Places of meeting for religious worship”, the “Assumed Ventilation and Cooling Strategy” is stated as “Closed windows”. Since closed windows would not provide ventilation or cooling, further explanation of this approach is required. Following this methodology, no night-time likely significant effects are identified for hospitals, hospices, nursing homes or hotels due to aircraft air noise. This can be seen in Figure 7.28 of the ES which shows that there are no areas within the 45dBLAeq,8h contour that experience a noise change of ‘moderate’ or greater (other than a small area within the airport boundary). In conclusion, a night-time assessment of noise sensitive non-residential receptors that include night-time operation (hospitals, hospices, nursing homes and hotels) has been undertaken and reported where relevant in the ES for all sources of noise. The ES identifies that no likely significant effects would occur other than a temporary night -time construction noise likely significant effect during the 09L airfield works for the Thistle London Heathrow Terminal 5. This is reported in the summary of effects in Table 7.52. The information provided therefore is sufficient for LBH to decide the application taking into account the assessment of effects related to these receptors. Hotels and offices It is not the case that hotels and offices are considered differently to sound recording and broadcast studios. Sound recording and broadcast studios are assessed using the same approach, with lower assessment thresholds for these receptor types identified in Table 7.23 and the upper assessment threshold defined in paragraph 7.5.94 of the ES. However, no broadcast studios or sound recording studios have been identified as experiencing likely significant effects based on the defined assessment methodology and hence no effects are reported in the ES. Assessment thresholds As noted in paragraph 7.5.97, the lower assessment thresholds are defined with regard to standards and guidance documents BS82335, HTM-08-016, Building Bulletin 937, and BCO8. As noted in paragraphs 7.5.92 to 7.5.94 the upper 5 British Standards Institution (2014). BS 8233: 2014 Guidance on sound insulation and noise reduction for buildings. London: B SI 6 Department of Health (2013) Health Technical Memorandum 08-01: Acoustics. [online] Available at: https://www.england.nhs.uk/wp- content/uploads/2021/05/HTM_08-01.pdf (Accessed June 2025). 7 Department for Education (2015). BB93: Acoustic Design of Schools – Performance Standards. [online] Available at: https://www.gov.uk/government/publications/bb93-acoustic-design-of-schools-performancestandards (Accessed June 2025). 8 British Council for Offices (2019) Guide to specification - Best practice for offices. London: British Council for Offices. LBH Noise Response Classification : Public © Heathrow Airport Limited 2023 2.5 ID LBH Question/Clarification Heathrow Response assessment threshold is defined with regard to Government aviation noise policy (paragraph 3.37 of the Aviation Policy Framework9). Where guidance specifies a range of indoor noise levels, professional judgement has been used to select a value within the range based on the anticipated sensitivity of the receptor to noise intrusion and the resulting external noise level criteria. Where guidance specifies indoor noise levels, these have been converted to outdoor free -field level depending on the assumed ventilation and cooling strategy. For naturally ventilated spaces a reduction of 15dB is assumed and with closed windows a reduction of 25dB is assumed. However, for purpose-built performing arts spaces and recording studios it is reasonable to expect that these receptors would have significantly higher existing insulation performance. This leads to the following assumed internal noise levels at the lower assessment thresholds which are in line with relevant standards and guidance documents as described below the table: Receptor type Daytime (07:00 – 23:00) Night-time Large and small auditoria; concert halls; sound recording and broadcast studios and theatres 35dBLAFmax or 25dBLAeq,16ha 35dBLAFmax or 25dBLAeq,8ha Places of meeting for religious worship 30dBLAeq,16hb N/A Courts; cinemas and lecture theatres 35dBLAeq,16hc N/A Museums; libraries; and community halls 40dBLAeq,16hd N/A 9 Department for Transport (2013). Aviation Policy Framework. [online] Available at: https://www.gov.uk/government/publications/aviation-policy-framework (Accessed June 2025). LBH Noise Response Classification : Public © Heathrow Airport Limited 2023 2.6 ID LBH Question/Clarification Heathrow Response Hospitals and other healthcare settings 40dBLAeq,16he 35dBLAeq,16he Schools; colleges; and registered nurseries 35dBLAeq,16hf N/A Hotels 35dBLAeq,16hg 30dBLAeq,8hg Offices 40dBLAeq,16hh N/A a - the assessment threshold for auditoria, concert halls, theatres and sound recording and broadcast studios has been informed by guidance for “good” conditions for indoor ambient sound levels for concert halls and theatres (25dBLAeq,T) and recording studios (20dBLAeq,T) from British Standard 8233:1999 Sound insulation and noise reduction for buildings – code of practice10. Whilst this standard has been replaced by the 2014 version 5, it contains guidance on noise levels that are not contained in the 2014 version and are still considered relevant and appropriate for application in this assessment. Given the specific sensitivity of recording studios to the ingress of noise, it is assum ed that any such receptor would have a building shell (including windows and ventilation penetrations) that would reduce external levels by at least 25-30dB. It is assumed that these spaces would have equal sensitivity during the day as when occupied at night. b - the assessment threshold for places of worship has been informed by guidance from British Standard 8233:2014 which recommends that indoor noise levels should not normally exceed 30-35dBLAeq,T for listening in places of worship. c - British Standard 8233:2014 does not provide guidance on indoor noise levels for courts, but the required activities and sensitivity to noise are considered to be similar to those of work requiring concentration of executive offices, for which a recommended range of 35-40dBLAeq,T is provided. Lecture theatres are considered to have a similar sensitivity to noise as courts by reference to both BS8233 but also Building Bulletin 93 Acoustic design of schools: performance standards (BB93). Whilst not applicable to further education premises, BB93 criteria are often adopted / adapted for 10 British Standards Institution (1999). BS 8233: 1999 Guidance on sound insulation and noise reduction for buildings. London: B SI. LBH Noise Response Classification : Public © Heathrow Airport Limited 2023 2.7 ID LBH Question/Clarification Heathrow Response this setting. Internal design criteria for cinemas in respect of external noise might typically be NR30Leq (~35 dBL Aeq,T) or less, however these uses tend to be purpose built with noise constraints in mind. d - the assessment threshold for museums and libraries has been informed by guidance from British Standard 8233:2014 which recommends that indoor noise levels should not normally exceed 40 -50dBLAeq,T for study and work requiring concentration in libraries, galleries and museums. Community halls have also been evaluated in the same way and are considered likely to be naturally ventilated. Where more sensitive uses are envisaged within a community hall, the propensity for closed windows and alternative means of ventilation and cooling were anticipated. e - the assessment threshold for hospitals have been informed by the criteria for noise intrusion from external sources for “Single-bed ward, single-bed recovery areas and on-call room, relatives’ overnight stay” in HTM 08-01 of 40dBLAeq,1h for daytime and 35dBLAeq,1h for night-time. f - recommended limits for indoor noise levels for schools are provided in Building Bulletin 93 Acoustic design of schools: performance standards. The assessment threshold for schools has been informed by the internal ambient noise level limit of 35dBLAeq,30min and 40dBLAeq,30min for naturally ventilated and non-naturally ventilated new build classrooms respectively, representing external levels of 55-60 dBLAeq,T. A precautionary lower external screening value was adopted to encompass the potential for shorter-term effects associated with alternation and the use of the LAeq,30min metric in BB93. Note also, that the internal criteria are also conservative because the schools are already existing and BB93 allows a 5dB in relation to the refurbishment of existing schools (i.e. 40dBL Aeq,30min and 45dB Aeq,30min for naturally ventilated and non-naturally ventilated classrooms respectively). g - British Standard 8233:2014 states that “the recommendations for ambient noise in hotel bedrooms are similar to those for living accommodation” and recommends for dwellings that internal ambient noise levels do not exceed 35dBLAeq,16h in areas of rest during the daytime and 30dBLAeq,8h in bedrooms during the night-time. h - the assessment criteria for offices has been informed by guidance from British Standard 8233:2014 which recommends that indoor noise levels should not normally exceed 35-40dBLAeq,T for work requiring concentration in executive offices. Similarly, BCO suggests an internal noise criterion of NR35 (~40dBL Aeq,T) for cellular offices in respect of external noise intrusion and building services noise respectively, resulting in the potential for a combined level of 43dBLAeq,T. Places of worship – cooling and ventilation LBH Noise Response Classification : Public © Heathrow Airport Limited 2023 2.8 ID LBH Question/Clarification Heathrow Response In respect of 'Places for religious worship' these premises are assumed to comprise two use cases having distinct acoustic requirements; prayer and worship areas with more onerous noise criteria but used for relatively short periods and other ancillary spaces used for longer periods but with less onerous noise criteria. In respect of the more onerous criteria (30dBLAeq,T) it is assumed that the spaces can be ventilated / cooled before and after activity by purge ventilation, therefore an assumption of closed windows is justified in the context of the more onerous use case. Furthermore, the consideration of ventilation and cooling is less relevant for places of worship, which tend to be older buildings, and less prone to overheating. 5 Parks and Open Spaces – Noise and Amenity: In Table 7.24 Stepped Assessment Methodology for Parks and Open Spaces, under “Impact of Proposed Development” it is recommended that the description of “Intermediate” be revised to “between 25% and 50% of the receptor area”. Under “Assessment”, it is unclear how a “change of 3-5 dB” being considered a likely significant effect differs from “a change of greater than 5 dB” being The description of intermediate is taken from the methodology as referenced in the footnote to Table 7.24 11. In practice the applied methodology would apply “Intermediate” to be “between 25% and 50% of the receptor area” as implied by the definitions of “Localised” and “Wide”. However, there are no receptors identified in the assessment where the area affected is forecast to be “Intermediate” as can be seen in Table A7.5.67 and A7.5.68 of Appendix 7.5 of the ES. The difference between the “3-5dB” and “greater than 5 dB” criteria leading to likely significant effects is described in Table 7.24 which notes that (emphasis added): “Where overall summer average noise exposure is found to change by 3 - 5 dB this may be considered a likely significant effect with a change of greater than 5 dB considered a likely significant effect.” This means that, for receptors screened into the assessment, changes of 3-5dB may lead to a likely significant effect, but the final assessment of significance is dependent on the application of additional factors as subsequently explained in Table 7.24. Changes of 5dB or greater are considered to lead to likely significant effects, regardless of additional factors. This approach to assessing 3-5dB change is demonstrated in paragraphs 7.8.255 and 7.8.258 in the ES which describe that Manor House Grounds is initially identified as having a potential likely significant effect due to a summer average noise change of 4dB, but the assessment concludes no likely significant effect when considering the 11 The Sizewell C Project, Volume 4 Southern Park and Ride, Chapter 8 Amenity and Recreation (2020). [online] Available at: https://infrastructure.planninginspectorate.gov.uk/wpcontent/ipc/uploads/projects/EN010012/EN010012 -002014- SZC_Bk6_ES_V4_Ch8_Amenity_and_Recreation.pdf (Accessed June 2025) LBH Noise Response Classification : Public © Heathrow Airport Limited 2023 2.9 ID LBH Question/Clarification Heathrow Response considered a likely significant effect. additional factors of existing ambient noise sources and the level of aircraft noise forecast to occur due to the Proposed Development. Heathrow is confident that the assessment of effects that is documented within the ES is sufficient for LBH to decide the application. 6 Modelling Methodology: It should be noted that ISO 9613-2 has recently been updated from the 1996 version referenced to a 2024 version which was published on 30 January 2024. While it is acknowledged that modelling work may have commenced prior to this change, it is recommended that, as a minimum, some comparative modelling be undertaken to compare the results from the two versions of the standard. The 2024 version of ISO 9613-2 was addressed in footnote 83 of the ES. As the footnote explains, a revision of ISO 9613-2 was published in January 2024. However, the revised Standard was only incorporated within the noise modelling software in June 2024. Because modelling to inform the ES had commenced long before this, incorporation of the updated software could not be used. Furthermore, the 1996 version is still relevant because of the reference to it within the Environmental Noise Directive (END) legislation. The new software does not yet have that status. The ISO 9613-2 methodology was used for the ground noise assessment, so any changes to this methodology would only affect the ground noise assessment. The assessment principally relies on noise change to identify new significant effects on health and quality of life and likely significant effects due to noise increases and decreases. As any methodological changes would be applied to calculations for both the ‘with alternation’ and ‘without alternation’ scenarios, the relative magnitude of noise change, and therefore the scale and location of identified effects are not expected to change significantly with the 2024 version. The key changes of relevance to the assessment in the 2024 version relate to attenuation terms for ground absorption and barrier effects, so the areas most likely to be affected by changes in methodology are those in Longford Village near the noise barrier. No significant effects on health and quality of life or adverse likely significant effects were identified for any receptors in Longford Village and only a significant beneficial effect was identified for a single residential property at night-time. No significant effects on health and quality of life or likely significant effects (adverse or beneficial) were predicted for any other receptor within the ground noise study area. Any changes in assessment results due to changes in calculation methodology are therefore not expected to change the scale of the effects identified, particularly in the context of this application where ground noise effects are limited compared to air noise effects. It should be noted that the 2024 version of ISO 9613-2 is currently under review by ISO Technical Committee 43/SC1 Working Group 56 “Quality assurance of noise calculation methods implemented in software” in terms of its accuracy LBH Noise Response Classification : Public © Heathrow Airport Limited 2023 2.10 ID LBH Question/Clarification Heathrow Response of implementation within modelling software. This is important as whilst the Standard has been revised there is currently no consensus on its implementation. For the reasons described above, it is therefore not considered necessary for comparative modelling to be undertaken and the information provided within the ES is sufficient for LBH to undertake their EIA and make their decision. In line with Action 9A of the NAP Heathrow are developing a Ground Noise Management Plan (GNMP). As part of GNMP measurements are being planned at receptors in Longford this year to support the formulation of the plan. As part of the GNMP it is proposed that these measures are carried out routinely and immediately after the introduction of Easterly Alternation. These measurements can be used to demonstrate and evidence the actual impacts of ground noise and noise-induced vibration of the Proposed Development. Noise effects in Longford principally arise from air noise rather than ground noise. However, whilst any additional eligibility under the QNS on account of ground noise is considered unlikely, any potential for actual ground noise effects to extend the area that qualifies already under the QNS would be captured and responded to as part of this work. 7 Operational: Aircraft Noise Induced Vibration: The approach proposed is considered appropriate. It would however be useful to include a reference to the investigations and measurements previously carried out by Heathrow Airport in a conservatory at the far end of Myrtl e Avenue. Details of the measurements made in the conservatory at Myrtle Avenue are contained in the report appended to this response. The report concludes that: “Thus only at properties of the order of 500m from a runway threshold are likely to experience vibration in the “Adverse comment possible” range, and then only in lightweight structures such as a conservatory.” This is consistent with the methodology in the ES of identifying receptors within 500m of the nominal start of roll location on Runway 09L as experiencing likely significant effects and suggests this is a conservative approach. 8 Quieter Neighbourhood Support (QNS) Sound Insulation Schemes: The full contribution up to a Full details of the QNS Residential Insulation Scheme are provided in Section 4 of Appendix 17.2 of the ES. That section notes that each property will be independently assessed to determine the insulation measures that will be most effective, noting that the scheme will incorporate some or all of the following: LBH Noise Response Classification : Public © Heathrow Airport Limited 2023 2.11 ID LBH Question/Clarification Heathrow Response maximum of £34,000 per dwellings requires some further information e.g. what £34,000 currently covers (particularly because it is used as a mitigation to avoid significant effects), whether this value increases over time in line with inflations, and what t he scheme covers in terms of replacement of noise insulation measures and regularity. - The supply and installation of replacement primary windows or secondary glazing and external doors. - The supply and installation of acoustically attenuated ventilation in eligible rooms. - The Installation of an acoustic quilt within the roof void. - Upgrading of ceilings within eligible rooms where practicable to provide an increased level of acoustic attenuation. The scale of expenditure per property is set out in Heathrow’s Noise Action Plan and scrutinised through that process. For the majority of eligible properties, the limit of £34,000 will be sufficient to provide the full cost of insulation for all eligible rooms. To date the average spend per property has been between approximately £11,000 and £18,000 depending on area and property type. This cost covers the survey and inspection work required, scaffolding, new acoustically specified windows and doors, ventilation system, loft insulation and ceiling overboarding where required. Should the expenditure required go beyond the limit of £34,000, this will be referred t o Heathrow’s Prioritisation Panel as a special case for determination. The limit of £34,000 per dwelling is adjusted for inflation and subject to periodic review and uplift by Heathrow. Where the dwelling has already been treated with acoustic glazing (double or secondary) or ventilation, Heathrow’s assessors will determine whether it remains effective or requires replacement under the scheme. 9 Home Relocation Assistance Scheme (HRAS): As above, further information is required on what £20,000 currently covers, and whether this value increases over time in line with inflation. The relocation assistance scheme applies to residential properties around Heathrow that are within the 2019 69 dB LAeq noise contour who wish to take the opportunity to move. Where the Proposed Development results in a residential dwelling being exposed to a summer average daytime noise exposure level of 69 dB LAeq,16hr but outside of the HRAS eligibility boundary (which is based on a 2019 contour) eligibility to HRAS will be extended. Eligible homeowners receive a payment made to their solicitor for moving cost such as stamp duty. To be eligible for the scheme, applicants must meet these criteria: - Own the property when applying. (If they currently live elsewhere, it must be the only property they own in the UK.) - Plan to move to a quieter area outside the boundaries of the scheme. LBH Noise Response Classification : Public © Heathrow Airport Limited 2023 2.12 ID LBH Question/Clarification Heathrow Response - Not retain a beneficial interest in, or right of occupation to, the property after moving. - Residents must have owned or be living in the property prior to 31 December 2022. Long-term tenants (with at least three years remaining on their lease) may also be eligible for assistance if the property they are renting is being sold. However, short-term tenants are not eligible for the scheme. On completion of the sale of the property, eligible homeowners will receive a lump sum of £10,000 plus 1% of the sale price of the property (totalling up to a maximum of £20,000). This will be subject to Land Registry checks and monies will be sent via BACS transfer to the homeowner’s solicitors within four weeks of completion. There is only one payment per property. The HRAS was updated as part of the Quieter Neighbourhood Support (QNS) programme review and will be reviewed as part of that process but will not be routinely adjusted for inflation. The number of eligible properties is relatively low and the scheme has been running for a couple of decades now. As the ES notes at paragraphs 7.8.97 and 7.8.98 and Appendix 7.5 Table A7.5.20, whilst residential properties in Poyle would be removed from the 69 dB LAeq,16hr contour, approximately 100 properties in Cranford and Stanwell Moor would be newly exposed above 69 dB LAeq,16hr due to the Proposed Development. All people and properties that are forecast to be exposed to levels above 69 dB LAeq,16hr in 2028 due the Proposed Development fall within the 2019 69 dB LAeq,16hr contour that underpins the HRAS. As such it is expected that all residential receptors exposed to levels of 69 dB LAeq,16hr in 2028 would be eligible for support under this scheme subject to the conditions of the scheme. Due to the proximity of the 2028 69 dB LAeq,16hr with Proposed Development contour to the 2019 HRAS scheme 69 dB LAeq,16hr contour, provision has been made to extend the eligibility the HRAS scheme in the event that dwellings become exposed to levels above 69 dB LAeq,16hr due to the Proposed Development and fall beyond current 2019- based eligibility boundary. 10 Construction Phase: Regarding paragraph 7.7.23, consideration of short-term temporary rehousing may be appropriate depending on the predicted construction phase noise levels so it is Heathrow will commit to standard provisions for providing short-term temporary accommodation for residents affected by construction noise if certain trigger levels are met. It is proposed that this commitment is secured through section 106 obligation. LBH Noise Response Classification : Public © Heathrow Airport Limited 2023 2.13 ID LBH Question/Clarification Heathrow Response recommended that it not be discounted. 11 Additional Mitigation Measures: The financial contributions towards noise insulation described in Table 7.31 should include details of the level of works that £3,000 and up to £12,000 are likely to provide to a recipient for context. Similarly, details of what the “bespoke insulation and ventilation” for schools is likely to include for the cap of £2.5m should be provided for context. Regarding Easterly Alternation Noise Mitigation Package for Noise Induced Vibration, examples of the level of works that £10 ,000 are likely to provide to a recipient should be included for context. Regarding Easterly Alternation Noise Mitigation Package for Parks and Gardens, it is unclear what the financial contribution of up to £250,000 will mean in terms of “enhancement” and hence additional details should be provided. The cost and recommended insulation solutions will vary from property to property, however, some indicative examples are given below. Properties eligible for the £3,000 scheme are exposed to between 54-60dBLAeq,16h and would be likely to meet internal criteria from BS8233 with standard glazing (i.e. existing glass retained but double-glazed unit), loft insulation and enhanced ventilation. This is in line with a £3,000 contribution which could cover, for example, surveys and installation of a ventilation product and 50m2 loft insulation. Properties eligible for the £12,000 scheme are exposed to between 60-63dBLAeq,16h and would be expected to meet internal criteria from BS8233 with replacement windows, loft insulation and enhanced ventilation. This is in line with a £12,000 contribution which could cover, for example, surveys and installation of a ventilation product, bathroom/kitchen ventilation, 50m2 of loft insulation and up to 8 units of secondary glazing. As these contributions are therefore in line with the typical costs required to meet the internal criteria of BS8233, the level of contribution is proportionate to the noise impacts for these noise exposures below SOAEL. With the case of schools, the precise works assessed to be needed will vary depending on the size of school buildings, existing insulation performance and other building fabric parameters. Based on Heathrow’s experience of providing insulation (upgraded windows and ventilation) to over 40 schools: - the cost of upgraded windows can range from approximately £6,000 to £900,000; and - the cost of ventilation can range from approximately £70,000 to £1.5million. Heathrow are confident, therefore, that it will be possible to provide upgraded windows and ventilation for the majority of types of schools within the £2.5million cap. As noted in Table 7.31, the additional funding of £10,000 for the Noise Induced Vibration mitigation package is to provide households with assistance towards the costs of mitigating the effects of noise induced vibration and will be most effective for dwellings with lightweight structures attached to their main residence. The types of work will be confirmed following an independent survey and assessment and will vary depending on the property. An example could be strengthening of reinforcing structural elements such as raised floors. LBH Noise Response Classification : Public © Heathrow Airport Limited 2023 2.14 ID LBH Question/Clarification Heathrow Response See response to ID28 for the Parks and Gardens query 12 Table 7.32 “Calculated night-time construction noise levels for Wright Way noise barrier construction works” references façade noise levels in terms of LAeq,5.5hr. In line with BS 5228, it is recommended that the time period of L Aeq be referenced to 1hr for night-time works. See response to ID1 13 Given that UAEL is predicted to be exceeded at Receptor 5 for four nights, consideration of an offer of short-term temporary rehousing (i.e. hotel accommodation) should be given in these instances. Heathrow will commit to providing short-term temporary accommodation for residents affected by construction noise if certain trigger levels are met. It is proposed that this commitment is secured through the section 106 obligation. 14 Table 7.34 “Predicted night-time noise levels for Phases 1, 2 and 3 new airfield infrastructure construction works” references façade noise levels in terms of LAeq,5.5hr. In line with BS 5228, it is recommended that the time period of LAeq be See response to ID1 LBH Noise Response Classification : Public © Heathrow Airport Limited 2023 2.15 ID LBH Question/Clarification Heathrow Response referenced to 1hr for night- time works. 15 Construction Phase: Construction Noise – 09R/27L Redundant Pavement Removal (Night- time): As noted above, it is recommended that the time period of LAeq be referenced to 1hr for night- time works. See response to ID1 16 Summary of Construction Phase Noise Assessment: The summary should also include that there are exceedances of the UAEL at Receptor 5 for four nights. The ES makes clear that there are short periods of UAEL exceedances at receptor 5 (four nights in total), see Graphic 7.2 and paragraph 7.8.5. The summary in paragraph 7.8.50 does not intend to reproduce the detail of the assessment but summarises the effects in terms of the NPSE aims and the identification of EIA likely significant effects , which includes receptor 5. 17 Assessment in Accordance with NPSE – Daytime Exposure: Details of what £34,000 would cover for the QNS in 2024 terms should be sought, along with a commitment for an annual inflationary increase. Regarding paragraphs 7.8.93 and 7.8.94, it is unclear whether reducing noise See response to ID8 with regard to the QNS £34,000 limit. In terms of meeting the second aim of the Noise Policy Statement for England (NPSE 12) there is nothing in the NPSE or its explanatory note that suggests meeting the second aim relies exclusively on noise reductions alone (with no 12 Department for Environment, Food & Rural Affairs (2010). Noise Policy Statement for England. [online] Available at: https://www.gov.uk/government/publications/noise-policy-statement-for-england (Accessed June 2025). LBH Noise Response Classification : Public © Heathrow Airport Limited 2023 2.16 ID LBH Question/Clarification Heathrow Response levels for some people while increasing noise levels for others meets the spirit of the second aim of the NPSE of mitigation and minimising the adverse impacts on health and quality of life between the LOAEL and the SOAEL. In addition, some of the net decrease in this band is due to some people moving to the above SOAEL band. Some justification around this approach should be provided. noise increase) rather than a reduction in total adverse impacts. In the Air Navigation Guidance (ANG 13) the UK Government stated at paragraph 3.4 and 3.5: “As stated in section 1.2(a) of this guidance, one of the government’s three key environmental objectives is to limit and, where possible, reduce the number of people in the UK significantly affected by adverse impacts from aircraft noise. For the purpose of assessing airspace changes, the government wishes the CAA to interpret this objective to mean that the total adverse effects on people as a result of aviation noise should be limited and, where possible, reduced, rather than the absolute number of people in any particular noise contour.” Whilst this is in the context of assessing airspace change, the concept of “limit and, where possible, reduce” is in line with the NPSE second aim to “mitigate and minimise” 14, and the clarification provided in the ANG makes clear that this should be interpreted in the context of the totality of adverse effects rather than looking at increases and decreases separately. This is then further emphasised in the Government’s Overarching Aviation Noise Policy Statement 15 (emphasis added): “The government’s overall policy on aviation noise is to balance the economic and consumer benefits of aviation against their social and health implications in line with the International Civil Aviation Organisation’s Balanced 13 Department for Transport and Civil Aviation Authority (2017). UK Air Navigation Guidance. [online] Available at: https://www.gov.uk/government/publications/uk-air-navigation-guidance-2017 (Accessed June 2025). 1414 The link between the NPSE concepts of mitigating and minimising and UK Government aviation noise objective concepts of limiti ng and reducing is also provided in the Overarching Aviation Noise Policy Statement Policy Paper which states “ In circumstances where there is an increase in total adverse effects, “limit” would mean to mitigate and minimise adverse effects, in line with the Noise Policy Statement for England. ” 15 Department for Transport (2023). Overarching Aviation Noise Policy. [online] Available at: https://www.gov.uk/government/publications/aviation-noise- policy-statement/overarching-aviation-noise-policy (Accessed June 2025). LBH Noise Response Classification : Public © Heathrow Airport Limited 2023 2.17 ID LBH Question/Clarification Heathrow Response Approach to Aircraft Noise Management. This should take into account the local and national context of both passenger and freight operations, and recognise the additional health impacts of night flights. The impact of aviation noise must be mitigated as much as is practicable and realistic to do so, limiting, and where possible reducing, the total adverse impacts on health and quality of life from aviation noise.” The point raised regarding the second aim of the NPSE was examined at the previous inquiry 16 and the Inspector found at para 1064 that the mitigation and minimisation of noise between LOAEL and SOAEL is achieved by measures other than noise insulation (the range of other measures which Heathrow takes to limit noise) and the second aim of the NPSE was met. This includes the provision of predictable respite through runway alternation on easterly operations as a result of the Proposed Development which itself is a mitigation according to the ANPS. The fact that the application would also achieve noise reductions for more people than the number of people who experience a noise increase (see ES Tables 7.43 and 7.45) also helps to confirm that the aims of the NPSE are met. As set out in the Planning Statement, these characteristics were known to the Inspector and Secretary of State in 2017 when the application was examined against the same NPSE tests and found to comply (IR paras. 1080 and 1122). 18 Assessment in Accordance with NPSE – Night-time Exposure: As above re: QNS and questioning whether reducing noise levels for some people while increasing noise levels for others meets the spirit of the second aim of the NPSE. Table 7.41 appears to be incorrectly formatted with levels of “55-57” shown as being between “LOAEL to SOAEL” and This is a presentational error and has not affected the assessment. The results of the assessment as per the data presented is unaffected and from this LBH are already able to take an informed view in deciding the application. 16 Department for Communities and Local Government (2017), Enabling works to allow implementation of full runway alternation during easterly operations Decision Letter APP/R5510/A/14/2225774 LBH Noise Response Classification : Public © Heathrow Airport Limited 2023 2.18 ID LBH Question/Clarification Heathrow Response therefore requires correction. 19 Assessment in Accordance with the NPSE – Conclusion: The above elements are not covered in the conclusion and it is recommended that they should be. Bullet point 3 states that “Although the number of people exposed to air noise above the daytime and night-time SOAEL is forecast to increase due to the Proposed Development in 2028, the increase is much smaller and most of these receptors are already eligible or will become eligible for a funded scheme of insulation under Heathrow’s QNS RIS“. It is recommended that some context be added to this e.g. what is the increase much smaller than. Additionally, demonstrated that the sound insulation scheme will avoid the significant effect is all cases is required. The ”much smaller” wording in bullet point 3 is in reference to the immediately preceding 2 bullet points, i.e. the quantum of the increase in the number of people exposed above the daytime and night -time SOAEL is much smaller than the quantum of the decrease in the number of people exposed between the LOAEL and SOAEL. It has been accepted in previous airport planning applications that providing noise insulation will avoid significant adverse effects on health and quality of life above SOAEL and will mitigate and minimise adverse effects on health and quality of life between LOAEL and SOAEL. For example, the appeal decision letter for the previous Easterly Alternation application 16 states at paragraph 1087: “Against this background I consider that the proffered mitigation between SOAEL and UAEL is consistent with the APF and would be sufficient to avoid significant observed adverse effects.” More recently, the Luton DCO decision letter17 states at paragraph 500: “The Secretary of State therefore agrees that the increased harm would ultimately be offset by noise insulation following rollout, which would satisfy the requirements of the NPSE, NPPF, PPGN and Policy LLP38 in the longer term to avoid effects above SOAEL and mitigate or minimise effects between LOAEL and SOAEL" It can therefore be concluded that where noise insulation is provided it can be demonstrated to avoid significant effects on health and quality of life above SOAEL and mitigate and minimise adverse effects on health and quality of life above LOAEL. Noise insulation for the adverse likely significant effects identified below 54dBL Aeq,16h is addressed in response to ID20. The extent to which impacts fall to be directly mitigated is to be assessed in the light of government policy. It is for the ES to forecast effects and describe the measures envisaged to avoid, prevent or reduce and, if possible, offset adverse likely significant effects. However, it is policy which determines the extent to which effects must be mitigated, 17 Department for Transport (2025), Application for the Proposed London Luton Airport Expansion Development Consent Order Decisi on Letter LBH Noise Response Classification : Public © Heathrow Airport Limited 2023 2.19 ID LBH Question/Clarification Heathrow Response guided by the aims of the NPSE. These matters are addressed extensively in the ES and in the Planning Statement, both of which establish that the mitigation package offered exceeds the requirements of government policy. 20 Likely Significant Effects – Daytime: Under Table 7.44, LSE-D07 includes a “very high” number of the population (15,500) who will experience “Exposure between proposed LOAEL and SOAEL and a ‘moderate’ 3 dB – 5.9 dB increase” but will have limited availability to noise insulation funding or, in the case of 12,100, will have no availability to noise insulation funding. Regarding paragraph 7.8.155, there is potential that on some days there will be a need for “having to keep windows closed most of the time”. As such, additional sound insulation provision should be considered for this area. Table 7.44 of the ES clearly shows that there will be a proportion of the population in Cranford and North Hyde for which likely significant effects (due to noise change) are identified that will not be eligible for noise insulation. This population are exposed to levels of noise just above the LOAEL (51.0 to 53.9dB) and whilst they would not be eligible for noise insulation they would experience predictable respite which would mitigate the adverse effects. It would not be proportionate or sustainable to provide noise insulation at such low exposures. There is no airport insulation scheme in the UK that provides insulation below 54dBL Aeq,16h, including major airport expansions such as the recently consented Luton DCO where the economic benefits of these projects allow for more expansive noise insulation programmes to be sustainable. Other airport expansion applications, such as London City Airport and Bristol Airport do not provide insulation below 57dBL Aeq,16h. It should also be noted that at these lower external noise levels, the effectiveness of sound insulation is likely to be very limited. A typical household construction (without a noise insulation package) would likely provide around a 25 dB reduction18, meaning that properties exposed between 51 and 54dBL Aeq,16h would experience internal noise levels of around 26 to 29dBLAeq,16h which is already below the target internal criteria in British Standard 8233 5 of 30 to 35dBLAeq,16h during the daytime. As such, the provision of additional insulation would have very limited effectiveness and is not considered sustainable. This is entirely consistent with the second aim of the NPSE which policy makes clear must be considered within the context of sustainable development. The Explanatory Note to the NPSE states at paragraph 2.24 (emphasis added): “The second aim of the NPSE refers to the situation where the impact lies somewhere between LOAEL and SOAEL. It requires that all reasonable steps should be taken to mitigate and minimise adverse effects on health and quality of 18 Building Research Establishment (2020), A review of insulation standards, building regulations and controls related to airport noise insulation schemes. Final Report. For the Independent Commission on Civil Aviation Noise LBH Noise Response Classification : Public © Heathrow Airport Limited 2023 2.20 ID LBH Question/Clarification Heathrow Response life while also taking into account the guiding principles of sustainable development (paragraph 1.8). This does not mean that such adverse effects cannot occur.” It is also entirely consistent with the findings of the 2017 decision, in which the Inspector found, and the Secretaries of State agreed that: - it would be disproportionate to expect Heathrow to change its airport wide insulation policy generally, or to offer a different package to those affected by easterly alternation (para. 1079); and - likely significant environmental effects are different from the significant effects on health and the quality of life referenced in the NPSE and it is not inappropriate that some significant environmental effects are not directly mitigated (para. 1064). The 12,000 referred to in the question are those who do experience an increase of at least 3dB but whose noise exposure would remain less than 54dBLAeq,16h (see Table 7.43). The paragraph then suggests that, whilst they don't qualify for noise insulation, they will need to keep their windows closed "most of the time". However, that observation comes from the PPG, it applies across the wide spectrum LOAEL to SOAEL and those in the 51 -54 dBLAeq,16h category are at the lowest end of that. The paragraph misquotes the PPG and the Noise Assessment (para 7.8.155) which are clear that this condition may only be necessary "some of the time". That is even more the case here as properties are affected by easterly alternation only c. 10-14% of the time. To put that into further context, aviation policy19 regards 54dBLAeq,16h as the approximate onset of significant community annoyance (para 3.17) (the concept of which was endorsed by the 2017 Inspector at DL para. 1119). This point is made in the Planning Statement at paras. 8.2.12 and 8.2.28. The PS also records that the 2017 Inspector found that the mitigation and minimisation of noise between LOAEL and SOAEL i s achieved by measures other than noise insulation (the range of other measures which Heathrow takes to limit noise) and the second aim of the NPSE is met (para. 1064) 21 Operational Phase: Annoyance, Sleep Disturbance and It is not possible to accurately calculate the number of people who will become highly annoyed or highly sleep disturbed as the exposure-response relationships can only be used to predict the percentage likelihood of a population being either highly annoyed or highly sleep disturbed for a given noise exposure. These relationships can then be 19 Department for Transport (2017). UK Airspace Policy: A Framework for the Design and use of Airspace. [online] Available at: https://www.gov.uk/government/publications/uk-airspace-policy-a-framework-for-thedesign-and-use-of-airspace (Accessed June 2025). LBH Noise Response Classification : Public © Heathrow Airport Limited 2023 2.21 ID LBH Question/Clarification Heathrow Response Monetised Outcomes: Annoyance: The number of people ‘highly annoyed’ is predicted to be lower with development than without, i.e. is beneficial, which is obviously positive. However, it would be useful to understand the number of people who will become ‘highly annoyed’ as a result of the proposed development. applied across a population within a study area to provide a statistical estimate of the total number of highly annoyed or highly sleep disturbed people within that population. As noise exposure increases, the likelihood of being highly annoyed or sleep disturbed increases and as noise exposure decreases, the likelihood decreases, but there is no trigger point above which an individual will become highly annoyed or highly sleep disturbed. The exposure -response relationships are derived from large scale studies and are not intended to be used to predict changes in high annoyance/high sleep disturbance at an individual level. This broad principle is explained by UK Government in the Air Navigation Guidance13 as follows (paragraph 3.5): “There is no one threshold at which all individuals are considered to be significantly adversely affected by noise. It is possible to set a Lowest Observed Adverse Effect Level (LOAEL) that is regarded as the point at which adverse effects begin to be seen on a community basis. As noise exposure increases above this level, so will the likelihood of experiencing an adverse effect. In line with this increase in risk, the proportion of the population likely to be significantly affected can be expected to grow as the noise level increases over the LOAEL.” It is considered that sufficient information has been provided for the informative appraisal of health impacts by the presentation of the change in total number of people highly annoyed and total number of people highly sleep disturbed as well as the change in number of people experiencing adverse effects on health and quality of life (between LOAEL and SOAEL) and the number of people experience significant adverse effects on health and quality of life (above SOAEL). 22 Operational Phase: Annoyance, Sleep Disturbance and Monetised Outcomes: Sleep Disturbance: Again, the reduction in the number of people ‘highly sleep disturbed’ is positive but it would be useful to understand the number of people who will become ‘highly sleep disturbed’ as See response to ID22. LBH Noise Response Classification : Public © Heathrow Airport Limited 2023 2.22 ID LBH Question/Clarification Heathrow Response a result of the proposed development. 23 Operational Phase: Annoyance, Sleep Disturbance and Monetised Outcomes: Monetised Outcomes: The TAG analysis effectively assumes ‘symmetry’ so a 1dB beneficial decrease exactly offsets a 1dB adverse increase. It is unclear whether there is evidence for this, particularly in the short to medium term. The TAG methodology is a Department for Transport (DfT) methodology and further information on the methodology and its evidence base is provided in the DfT’s Guide to WebTAG Noise Appraisal for non -experts20. As noted in the ES, TAG is not a comprehensive assessment of noise impacts and the monetised outcomes are presented only as informative appraisals. It is not the case that the TAG analysis assumes symmetry, as the exposure response relationships that are used in the methodology are not linear. 24 Operational Phase: Aircraft Air Noise – Non- Residential Noise Sensitive Receptors: As noted above, the justification for excluding hotels and offices on the basis that they are commercial enterprises does not make sense when compared with other receptor types such as Theatres, Cinemas, and Sound recording and broadcast studios which It is not the case that hotels and offices are excluded from the assessment. Hotels and offices have been fully assessed, and the detailed results are presented in Section 9 of Appendix 7.5 of the ES. The outcome of the assessment for hotels and offices is summarised in Table 7.53 of the ES. 20 Department for Transport (2017), Guide to WebTAG Noise Appraisal for non-experts. [online] Available at: Guide to WebTAG noise appraisal for non- experts (Accessed June 2025)

Heathrow Airport Limited Registered in England No: 1991017 Registered Office: The Compass Centre, Nelson Road, Hounslow, Middlesex TW6 2GW Heathrow Airport Limited The Compass Centre, Nelson Road, Hounslow, Middlesex TW6 2GW T: +44 (0)844 335 1801 W: heathrow.com LB Ealing Heathrow response LB Ealing’s objection to the application does not acknowledge that the application responds to and is required by Government policy. Or that it is required in order to bring equity to the distribution of noise around Heathrow. It is understandable that the Council would wish to preserve the status quo in which LB Ealing experiences less overflying on easterly operations, at the expense of other communities – but any assessment should recognise the policy background and the balance which the application is seeking to strike. The objection also does not recognise that these matters have been the subject of previous proposals which were considered by the Secretary of State and approved because of the “overriding public benefit” that they will provide. At that time, the mitigation offered to Ealing residents was significantly less. A balanced assessment should acknowledge these matters. Welcome the opportunity to work with Heathrow …transparent roadmap Heathrow is committed to working closely with its local authorities and fully engaged in the joint working facilitated by CISHA for the Easterly Alternation project. In regards, to future projects at Heathrow there will be a programme of engagement with all key stakeholders, which the London Borough of Ealing will be part of. Heathrow will share further information when they are able to. For example, Heathrow has committed to working collaboratively with Local Authorities to share and exchange information as set out in their Noise Action Appendix 4 Plan to aid land use planning and noise mitigation. Revised contours have a sharp node NW of the airport – this fundamentally means that 30% of total departures will affect the vast majority of Ealing residents in Southhall, Hanwell, ….Greenford It is a misconception that all easterly departures (30%1 of the total 480,000 (that’s movements, not just departures)) will affect the likes of Southall, Hanwell, Ealing, Acton, Perivale and Greenford. Not all easterly departures are routed north over Ealing. BPK and ULTIB departures are Heathrow’s only northbound SIDs (affecting those areas), which during 2023 and 2024 accounted for only 30% of easterly departures (2023 - 15%/15% and 2024 – 15%/15%). To put that into context: - The total permissible movements at Heathrow annually are 480,000; half of these are departures – ie 240,000; - For c.30% of the time, Heathrow operates on easterlies – ie 72,000 departures; - c.30% of these would route north over Ealing – ie 21,600; - But only for 50% of the time over newly affected area, due to alternation – ie 10,800 movements (so, using the 2023/24 split, that’s 4.5% of total departures). - This also means that residents being overflown today would benefit from a reduction of c.10,800 movements due to alternation. To put this into perspective, communities affected by westerly operations are affected by departures 35% of the time and, unlike Ealing communities, many of those communities are also affected by arrivals. 1 Easterly operations occur up to a maximum of 30% of the time in any one year, but often occur much less frequently, c.10% of the time, depending on climatic conditions. The largest exposure during nighttime will adversely affect residential developments, care homes and hospitals – particularly by affecting residents’ ability to fall asleep and an increased risk of awakening, leading to sleep deprivation. With at least 16 departures during the night. The vast majority of newly overflown residents shall be regularly exposed to aircraft noise at night due to late departures and activity starting at 04.30. The main change during the night-time period (23:00 to 07:00) due to easterly alternation which would affect Ealing is a change in scheduled operations, which commence at 06:00. Activity commencing at 04:30 relates to arrivals, which do not overfly Ealing. There are 16 departures scheduled during the night-time period in the 06:00 to 07:00 hour of which around 30% use the northbound routes over Ealing. Therefore, around five departures will overfly Ealing during easterly operations in the ‘night-time’ period. Even this number is not all new to Ealing, with easterly alternation, scheduled departures will be split equally between Heathrow’s northern and southern runways and their corresponding departure routes. The northbound departure routes from both the southern and northern runways both currently overfly parts of Ealing. These routes are presented in Figure 7.29 of the Environmental Statement along with the Ealing borough boundary. The northbound routes are denoted ‘ULTIB’ and ‘BPK’. Easterly alternation will result in half of these departures utilising the northern runway departure routes with a corresponding reduction in departures on the southern runway departure routes. As such, some parts of Ealing will observe an increase of around 3 aircraft departures in the 06:00 – 07:00 hour with some parts of Ealing observing a corresponding reduction. Whilst early morning arrivals are scheduled, departures can occur after 23:00 due to late running. The noise assessment has considered a worst-case scenario whereby, based on trends observed at the Airport, eleven aircraft scheduled to arrive or land before 23:00 have been modelled in the night-time period. Of these aircraft, 9 are departures and all typically operate southbound routes and therefore do not affect Ealing. Night-time noise effects on sleep, including awakenings, are assessed based on average noise conditions. This means that such assessments must consider the amount of time the Airport is operating in both an easterly and westerly direction and how it uses its runways. Easterly operations occur for around 24% of the time during the night-time period. Therefore, Easterly alternation would on average result in a change of less than one departure on either the northern or southern runway northbound routes during early morning departures. Government policy requires night-time aircraft noise to be considered where noise exposure is above the Lowest Observed Adverse Effect Level (LOAEL). This is based on average conditions. The night- time LOAEL with and without easterly alteration is shown in Figure 7.28 of the Environmental Statement. Neither contour is forecast to extend into the Ealing borough boundary. Government policy also allows changes in night-time aircraft noise to be presented using the ‘N60’ metric. This metric represents the number of aircraft events above 60 dB LASmax on average at night. These metrics, referred to as ‘Number Above’, are used to help describe and show changes in the number of maximum noise level events above a certain maximum noise level. Guidance issued by the Civil Aviation Authority states that the N60 should be presented for five events or more. Due to the use of the northbound routes and the east-west modal split at Heathrow, the night-time N60 contours as presented in Figure 7.5.7-WoD and Figure 7.5.7-WD do not extend into Ealing under departure routes. Section 4 of Appendix 7.5 of the Environmental Statement provides an indicative assessment of changes in objective awakenings. Figure 7.35 of the Environmental Statement shows that Ealing falls beyond the outer most contour presented (5 N60 events) and that within this contour the expected change in awakenings would be less than one per night on average. Noise contours are misleading – maximum sound pressure levels and the number of events during the night are more relevant. Aircraft noise is subject to Government policy and assessment guidance which prescribes the use of average equivalent exposure level contours i.e. LAeq,16hr and LAeq,8hr for day and night-time periods respectively. These metrics have been adopted based on the findings of studies demonstrating these metrics best corelate exposure to aircraft noise with annoyance and sleep disturbance. These metrics and associated Government policy thresholds form the ‘primary’ basis of assessing the effects of changes in aircraft noise. However, as described above, Government has also adopted the use of ‘Number Above’ metrics to help articulate impacts and describe changes that may occur due to a change in runway or airspace operations. For night-time operations, the N60 metric is presented in the Environmental Statement with the N65 metric (the number of aircraft events above 65 dB LASmax on average during the day) is also provided. The N65 metric is particularly useful in describing impacts. This metric is presented for both average conditions (in line with Government policy) and to articulate the change that would be observed due to Easterly Alternation during a busy easterly day. This information is provided in Figure 7.18 and Figure 7.21 of the Environmental Statement, respectively. These figures show that during the daytime some parts of Ealing would experience an increase in N65 events with other parts of the Borough experiencing a decrease. These changes are a consequence of the Airport alternating its runways at 15:00 which seeks to equitably distribute air traffic between the northern and southern departure routes to provide noise respite. The position at night is described above. Assessment should use a 1-hour day and a 15-minute night for the assessment in line with Ealing’s SPG10. As outlined above, Government policy in relation to aircraft noise assessment is based on effects in a 16-hour daytime period from 07:00 to 23:00, and an 8-hour nighttime period from 23:00 to 07:00. There is no policy or evidential basis for the assessment of aircraft noise against a 1- hour daytime or 15-minute night-time metric. We note that Ealing’s SPG10 was written prior to the adoption of the Noise Policy Statement for England (2010), the Aviation Policy Framework (2013), and the Air Navigation Guidance (2017) which are the key policy documents in relation to the assessment of aircraft noise. None of those documents use or reference 1-hour or 15- minute contours. Heathrow should adopt the Agent of Change principle. LB Ealing may have misunderstood the Agent of Change principle. As set out in the London Plan, at Policy D13, the responsibility for protecting against noise nuisance from an established source lies on the noise sensitive development nearby, which must be constructed to a sufficient standard. The purpose of the principle is to protect important economic activity. As D13 explains: “Development should be designed to ensure that established noise and other nuisance-generating uses remain viable and can continue or grow without unreasonable restrictions being placed on them.” The Agent of Change principle protects, rather than undermines Heathrow’s ability to comply with government policy by using established flight paths to achieve easterly alternation. The policy to support and bring forward Easterly Alternation is not new, and LB Ealing will have been aware of it, and should have planned accordingly. The EIA does not clarify what increase in sound level the listed areas in Ealing will experience from the proposed development. This is not correct. The Environmental Statement is accompanied by a series of figures which articulate the changes associated with easterly alternation using a range of noise metrics. These are presented throughout Volume IV Appendix 7.5. These figures are presented with the London Borough of Ealing boundary shown. • Figure 7.5.4 presents the expected change in summer average daytime LAeq,16hr in line with policy • Figure 7.5.5 presents the exposed change in summer average night- time LAeq,8hr in line with policy These figures present the primary policy metrics for assessing the effects of the Proposed Development. • Figure 7.5.25 presents the change in LAeq,16hr noise level during a busy easterly day for information purposes • Figure 7.5.26 presents the change in LAeq,8hr noise level during a busy easterly night for information purposes • Figure 7.5.29-1 presents the change in N65 during a busy easterly day for information purposes • Figure 7.5.29-2 presents the change in N60 during a busy easterly night for information purposes These figures help describe changes in aircraft noise levels and events during easterly operations because of Easterly Alteration. • Figure 7.5.36 presents LAeq,8hr (alternation period) noise levels during an 8-hour period of easterly runway operations departing from the northern runway and landing on the southern runway for information purposes i.e. as would occur for 8- hour with easterly alternation • Figure 7.5.37 presents LAeq,8hr (alternation period) noise levels during an 8-hour period of easterly runway operations departing from the southern runway and landing on the northern runway for information purposes These figures show the levels of aircraft noise during an 8-hour runway alternation period describing the levels of noise during specific runway operations. Appendix 7.8 of the Environmental Statement provides more detailed assessment areas described as ‘Community Focused Areas’. This appendix and its associated figures present a localised assessment of changes due to easterly alternation using metrics discussed within Chapter 7 of the Environmental Statement. The following communities within Ealing are represented in the Community Focus Area analysis, as follows: • Acton – Focus Area E5 • Acton Green – Focus Area E9 • Dormer’s Wells – Focus Area E4 • Ealing – Focus Area E5 • Greenford – Focus Area E1 • Hanwell – Focus Area E4 • North Acton – Focus Area E2 • Northolt – Focus Area E1 • Norwood Green – Focus Area E8 • Perivale – Focus Area E2 • South Acton – Focus Area E5 • West Acton – Focus Area E5 • West Ealing – Focus Area E4 • Southall – Focus Area E4 These figures show that locations such as Southall and Dormer’s Wells would experience some increase in aircraft noise and aircraft noise events, whereas Ealing would experience a decrease. With reference to Figure 7.5.2-WD of the Environmental Statement which presents the summer average LAeq,16hr noise metric with Easterly Alternation, this shows that the borough of Ealing would be exposed to aircraft noise at or below levels of 54 dB LAeq,16hr. This level of aircraft noise is considered by Government as the “approximate onset of significant community annoyance”. All changes due to Easterly Alternation, increases or decreases, should be considered in this context. The impact is likely to breach the requirements of standards for internal environments and in external amenity areas, contrary to BS8233. Mitigation measures are necessary, including operational controls, a night time ban and measures to ensure an upper value of 55 dB for external areas. British Standard BS8233:2014 ‘Guidance on sound insulation and noise reduction for buildings.’ Chapter 1 of the BS8233:2014 standard describes it scope and associated domain of use. It states that: “This British Standard provides guidance for the control of noise in and around buildings. It is applicable to the design of new buildings, or refurbished buildings undergoing a change of use, but does not provide guidance on assessing the effects of changes in the external noise levels to occupants of an existing building.” BS8233:2014 is not an applicable standard for assessing the impacts of a change in external noise levels on existing buildings. The standard is however applicable to the assessment of existing noise impacts on new or refurbished buildings as per SPG10 (albeit SPG10 is based on a superseded version of the BS8233 standard). Heathrow is a ‘noise-designated’ airport under the Civil Aviation Act 1982. This means that the Government has competence and authority for determining and introducing noise mitigation measures and noise-related operating restrictions at Heathrow Airport. Night flying restrictions are set by Government and reviewed every 5 years under this Act. These restrictions were most recently reviewed and determined in December 2024. Other measures such as runway alternation are also set down by Government in its role under the Act. The noise management and mitigation measures in place at Heathrow Airport and their origin (i.e. through the Civil Aviation Act 1982, planning controls, or voluntarily) are set out in Volume III Appendix 7.2 of the Environmental Statement. Based upon standard thermal double glazing and non-acoustic ventilation not exceeding 4000mm2 (equivalent area) per room, an external (free-field) to internal (reverberant) sound reduction of 26dBA can be safely assumed for normally constructed residential properties. BS 8233 advises internal noise criteria of 35 dBLAeq,16h and 40dBLAeq,8h for the daytime and night-time respectively. The corresponding external levels are consequently 61 dBLAeq,16h and 56 dBLAeq,8h, below which BS8233 internal noise criteria would be readily achieved. Importantly, where external levels are higher, BS8233 criteria can still be achieved, but would likely require enhanced building envelope sound insulation measures, which would represent a standard well-rehearsed approach. It is important to stress that BS8233 applies only to new buildings or buildings undergoing a change of use. The standard is not a requirement or expectation by Government as part of noise insulated schemes. With reference to Figure 7.5.2-WD and Figure 7.5.3-WD of the Environmental Statement which present the summer average LAeq,16hr (daytime) and LAeq,8hr (night-time) noise metrics with Easterly Alternation, this shows that the borough of Ealing would be exposed to aircraft noise at or below levels of 54 dB LAeq,16hr and 45 dB LAeq,8hr. This level of noise exposure is well below the values of 61 dB dBLAeq,16h and 56 dBLAeq,8h advised above. Consequently, the Proposed Development would not impose abnormal constraints upon future residential development in terms of achieving BS8233 internal noise criteria. Cumulative effects – the ES has not taken account of cumulative effects in construction, or operation. A construction noise assessment is provided within Chapter 7 of the Environmental Statement, supported by further detail and figures in Volume III Appendix 7.4 and Volume IV Appendix 7.4. The construction noise effects identified as part of the Proposed Development are localised to Longford. There is no potential for construction noise from any other construction project within Ealing to result in a cumulative effect. The operational noise assessment has regard for all operational noise and not just the noise associated with easterly operations. The assessment has considered the combined noise impact of air and ground noise sources which is presented in Chapter 7, and Volume III Appendix 7.7 however other sources of noise namely road and rail traffic will also affect receptors in Ealing. Such sources will become more influential on the overall noise climate as aircraft noise gets lower as will be the case in many parts of the Borough. Spatial planning and housing delivery in Ealing will be affected. For the reasons set out above, forecast aircraft noise levels within Ealing would not impact on the suitability of areas for housing delivery. We note that SPG10 adopted noise contours based on a 2016 forecast ‘average worst mode on day’ level. The corresponding contours are provided in Appendix 5 of SPG10. These contours show noise levels of worst-case mode levels of 57 dB LAeq,16hr extending through Ealing town centre. SPG10 utilises these contours as the basis of Noise Exposure Categories (NECs) which advise how aircraft noise is to be treated within planning applications. We understand that the SPG10 contours are based on an easterly day of 09R, southern runway departures. Easterly day LAeq,16hr contours with and without Easterly Alteration are available in Figure 7.5.23- WD and Figure 7.5.23-WoD of the Volume III Appendix 7.5 of the Environmental Statement, respectively Figure 7.5.36 also provides a worst-case single mode LAeq,8hr (alternation period) contour based on an 8-hour period of 09L departures, as would occur with Easterly Alternation. In all figures referenced above, the aircraft noise levels and extents of the contours provided in the Environmental Statement are at worst consistent or smaller than those provided in Appendix 5 of SPG10 for equivalent noise level values. We note that Appendix 3 of SPG10 states that “It should be noted that the adopted worst mode contours relate to current conditions of operation, whereby no easterly flying takes place over the village of Cranford during the daytime period. In the event of this mode of operation changing, new worst mode one day forecast contours would be commissioned and adopted by the Borough, since new areas of the Borough would be affected by overflying.” Taking into account the noise contours provided in the Environmental Statement and the guidance provided in SPG10, Easterly Alternation is not a basis to restrict housing development. Action 6 of Heathrow’s Noise Action Plan 2024 – 2028 states that Heathrow “... will share the forecast noise contour outputs agreed upon in the MoU with local authorities and exchange information regarding their local development plans and our forecasting outputs to collaboratively reduce sleep disturbance and support land use planning.” Heathrow is happy to provide up to date forecast information to support the application of its guidance. Ealing’s objection does not acknowledge the noise insulation offer set out in the application, which (as explained in the Planning Statement at paragraph 8.2.76), significantly exceeds the requirements of government policy, and the mitigation package which the SOS considered appropriate when easterly alternation was last considered in 2017. With respect, it is for government policy to establish noise policy and noise mitigation requirements. These are met and exceeded in the application. Bhoseok Nam Head of Town Planning & Consenting Bhoseok.Nam@heathrow.com Tel. +44 7713 075 454

Heathrow Airport Limited Registered in England No: 1991017 Registered Office: The Compass Centre, Nelson Road, Hounslow, Mid dlesex TW6 2GW Heathrow Airport Limited The Compass Centre, Nelson Road, Hounslow, Middlesex TW6 2GW T: +44 (0)844 335 1801 W: heathrow.com Heathrow response to LB Hounslow reps on Easterly Alternation London Borough of Hounslow Heathrow responses 1.1 This letter serves as a holding response from the London Borough of Hounslow (Hounslow) regarding the proposed expansion at Heathrow. While Hounslow accepts the principle of the proposal, further detailed information is required to assess and agree on appropriate mitigation measures before a formal position can be reached. 1.2 Hounslow has significant concerns about the cumulative impact of increased aircraft noise, particularly on deprived communities that will be newly exposed to heightened noise levels. In line with paragraph 96 of the National Planning Policy Framework ( NPPF), additional mitigation is required to address existing inequalities and ensure that the health and well -being of affected residents are protected. 1.3 A key principle of planning policy is the Agent of Change, which places the responsibility on Heathrow Airport Limited (HAL) to mitigate noise impacts and provide appropriate and effective long-term compensation for affected communities. The current mi tigation package does not adequately address the real -life impacts of increased noise exposure, particularly for socially and economically vulnerable groups. As set out in the London Plan, at Policy D13, the responsibility for protecting against noise nuisance from an established source lies on the noise sensitive development nearby, which must be constructed to a sufficient standard. The purpose of the princip le is to protect important economic activity. As D13 explains: “Development should be designed to ensure that established noise and other nuisance-generating uses remain viable and can continue or grow without unreasonable restrictions being placed on them.” The Agent of Change principle protects, rather than undermines Heathrow’s ability to comply with government policy by using established flight paths to achieve easterly alternation. The policy to support and bring forward Easterly Alternation is not new, and LB Hounslow will have been aware of it. 1.4. Key issues that require further clarity and revision include: 1.4.1. Cumulative Noise Impact on Deprived Communities: Areas such as Heston and Cranford, which already experience high levels of deprivation and health inequalities, will be disproportionately affected. The mitigation Environmental Statement, Volume II Chapter 9: Public Health assessment Section 9.7 specifically considers how the distribution of noise affects particular community areas, including in relation to their deprivation and vulnerable population profiles. Envir onmental Statement, Volume III Appendix 9.2 Public Health Figures 9.9 and 9.10 set out Appendix 5 July 2025 London Borough of Hounslow Heathrow responses packages must be strengthened to reflect equity considerations. information in relation to deprivation. Environmental Statement, Volume II Chapter 9: Public Health sets out health site-specific study areas (HSSSAs) to provide a detailed understanding of the distribution of effects. The following overlaps with Equal Opportunity Areas are noted: • Hounslow Equal Opportunity Area ‘North Hyde and north Cranford’ has a high degree of overlap with HSSSA1 (an adverse effect). • Hounslow Equal Opportunity Area ‘North Feltham & Hatton, Feltham East and Feltham Central’ has a high degree of overlap with HSSSA4 (a beneficial effect). • Hounslow Equal Opportunity Area ‘Hanworth North’ has partial overlap with HSSSA4 (a beneficial effect). • Hounslow Equal Opportunity Area ‘Cranford and Hesting North’ has a small overlap with HSSSA2 (an adverse effect) and a small overlap with HSSSA4 (a beneficial effect). Mitigation is further discussed in Environmental Statement, Volume II Chapter 7: Noise and Vibration. The Chapter 7 and Chapter 9 assessment shows how the redistribution o f noise is associated with beneficial effects in some areas and adverse effects in other area s, with effects limited to around 10% of the time during the summer, and around 14% over the course of a year, with no change in the ATM cap at Heathrow as part of the Proposed Development. Environmental Statement Appendix 8.1 Equality Statement sets out baseline information on the potential for disproportionate and differential effects, including in relation to the HSSSAs. The combined effects of the Proposed Development that may be experienced by the same communities (i.e. in-combination effects) are assessed in Chapter 9 section 9.7. July 2025 London Borough of Hounslow Heathrow responses The cumulative effects with the proposed Development and other projects are assessed in Environmental Statement, Volume II Chapter 13: Cumulative Effects. Environmental Statement, Volume II Chapter 9 concludes that, whilst there are a range of beneficial and adverse influences due to the Proposed Development, overall, the effect for public health is likely to be neutral in EIA Human Health terms. This conclusion reflects that a range of noise metrics indicate net benefits and the potential for adverse effects, including for vulnerable groups, is addressed through targeted mitigation. This mitigation includes the Longford Noise Barrier, QNS extension and the Easterly Alternation Noise Mitigation Package, the latter including residential, open space and school measures. The Proposed Development is fundamentally about achieving a more equal distribution of aviation emissions (principally air noise) around the Airport, and this is evident from, for example, comparing Figure 7.5.23 WoD and Figure 7.5.23 WD (Volume IV of the Environmental Statement). The changes facilitate short - to medium -term predictable respite benefits under easterly operations for communities that are currently disadvantaged by the Cranford Agreement. In the long-term, once there is normalisation of the e xperience of full runway alternation for all communities, predictable respite is likely to represent an improved position for health equity around the Airport. Environmental Statement, Volume II Chapter 9 paragraphs 9.7.130 to 9.7.135 include a specific consideration of equity in the context of the Proposed Development and its noise changes. July 2025 London Borough of Hounslow Heathrow responses 1.4. Key issues that require further clarity and revision include: 1.4.2 Providing Equity in Mitigation: The Easterly Alternation Mitigation Scheme needs to consider the demographics affected by noise impacts and ensure that the scheme reflects the deprivation levels prevalent in areas adversely affected by additional noise. See Heathrow response to comments to 4.7 Equalities Weighting and 4.9.6., 4.9.7 and 4.9.8 below. 1.4. Key issues that require further clarity and revision include: 1.4.3 Gaps in Noise Insulation Coverage: The eligibility criteria for mitigation does not account for all affected properties, leaving many exposed to unacceptable noise levels without adequate mitigation. Heathrow's mitigation proposals are compliant with Government policy and go beyond Government policy in two ways - eligibility criteria and the financial contribution. The foundation of the mitigation proposals is Heathrow’s Quieter Neighbourhood Scheme (QNS), which forms part of Heathrow’s Noise Action Plan which was adopted and approved by the Government in October 2024. 1.4. Key issues that require further clarity and revision include: 1.4.4 Impacts on Schools, Libraries & Community Buildings: The assessment does not fully consider non-residential receptors, despite clear evidence that noise pollution affects child development, learning environments, and public health. Environmental Statement, Volume II Chapter 7: Noise and Vibration and Chapter 9: Public Health both include specific discussion of nurseries, schools, libraries and community buildings. For example, Chapter 9 section 9.7 has sections on Community Infrastru cture Public Health Implications for both construction and operation. Chapter 9 section 9.7 also has a specific section on Educational Attainment Public Health Implications during operation, recognising the importance of development and learning environments for public health. 1.4. Key issues that require further clarity and revision include: 1.4.5 Long-Term Monitoring & Compensation: The current compensation expires in 2028, failing to account for the long-term nature of noise impacts. Hounslow expects continuous monitoring, with mitigation and compensation available in perpetuity while flights over Cranford continue. Heathrow is committed to continuing noise mitigation - and to monitoring to ensure that mitigation remains consistent with the effects of easterly alternation. Heads of Terms have been prepared for a S.106 agreement with LBH, which commit to monitoring – and which are attached. 1.4. Key issues that require further clarity and revision include: 1.5 At this stage, Hounslow requires further technical assessments, revisions to noise modelling, and a commitment from HAL to deliver To discuss, following our meeting it is not clear what further information is requested, as the submitted assessment is considered to be comprehensive. There is always more detail that can be sought but we believe the ES is both extensive and complete in its scope – giving LB July 2025 London Borough of Hounslow Heathrow responses a more comprehensive mitigation package before a final position can be taken. Hillingdon more than sufficient information to enable determination of the application. 2.2. Previous Planning Application 2.3.2. Whilst the principle of flights over Cranford was established in the revocation of the Cranford Agreement in 2009. This application will facilitate a significant increase in aircraft movements across large swathes of Hounslow that were previously less or not affected by aircraft noise. The proposal for easterly alternation has the same principal effect and characteristics as that previously accepted by the SoS. The ES demonstrates that significant effects would be experienced due to the scheduled use of the 09L BPK/ULTIB departure route. Whilst significant effects have been identified, these are a consequence of providing wider benefits to other communities as pa rt of redistributing noise around the airport. The ES demonstrates that, for those communities experiencing adverse likely significant effects, these are associated with operations that would occur 10 -15% of the time and would be associated with the provis ion of respite elsewhere. Additional mitigation is proposed beyond that found necessary by the SoS. 2.4. Scope of this Response 2.4.1. The London Borough of Hounslow will not comment on the physical infrastructure proposed at Heathrow Airport. Instead, this response focuses on the Environmental Impact Assessment, conclusions and outcomes, as well as the proposed mitigation measures under the Easterly Alternation mitigation scheme and the draft Section 106 agreement. Noted. 3. Policy Context 3.1. The supporting Planning Statement identifies some of the key policy frameworks underpinning the decision -making process. However, it is the Council's view that the following should be considered in the decision -making. 3.2 Local Plan 3.2.1. The London Borough of Hounslow's Local Plan 2015 (HLP) is not cited in the planning application and is essential to the consideration of this proposal. 3.2.2. HLP Policy EC3 clearly states: "We [Hounslow] will encourage a more sustainable Heathrow Airport by wor king with the airport operator and other partners to reduce Noted. The application is considered to be policy compliant. The Hounslow policies do not introduce additional issues beyond those which are considered in the planning application. July 2025 London Borough of Hounslow Heathrow responses environmental impacts, whilst recognising the role of the airport in the local economy." 3.2.3. In accordance with this, development proposals for the airport are expected to: h) Demonstrate that air and noise pollution from aircraft movements, the airport's infrastructure and transport to and from the airport avoid adverse impacts on the Borough; n Assess and illustrate the noise impacts of any development proposal, including the use of alternative noise metrics (i.e. alternative in addition to the dB LAe q 16h); j) Demonstrate that all reasonable steps have been taken to reduce the risk of safety related incidents occurring; k) Demonstrate that adverse impacts on the Green Belt, Metropolitan Open Land, open space and biodiversity are avoided; l) Demonstrate that adverse impacts on the borough's transport network and the wider strategic transport network are avoided; m) Have a positive impact on the local economy; and n) Be compliant with the government's Circular 01/2010 on control of development in airport Public Safety Zones. 3.2.4. The London Borough of Hounslow concluded their Regulation 19 Proposed Submission Local Plan in October 2024 and the Council is currently reviewing the comments in preparation to submit the proposed Plan to the Secretary of State in Spring 2025. 3.2.5. The supporting text for emerging Policy EC3 outlines that: "Concerted efforts must be made to mitigate against the direct negative effects of airport operations on our communities - particularly in relation to noise; poor air quality; congestion on the transport network and loss or degradation of green space and biodiversity. " 3.2.6. The emerging policy on Heathrow (Policy EC3) carries forward the previous policy wording of the adopted Plan and should carry moderate weight. Noted. 3.3. Agent of Change Principle 3.3.1. It is the Council's view that the applicant's Planning Statement does not duly consider See Heathrow response to 1.2 and 1.3. July 2025 London Borough of Hounslow Heathrow responses changes to the National Planning Policy Framework (NPPF) since the determination of the previous planning application and subsequent appeal. 3.3.2. Specifically, the Applicant's Planning Statement stays silent on Paragraph 200, the introduction of the Agent of Change Principle in national policy. Paragraph 200 states that: "Planning policies and decisions should ensure that new development can be integrated effectively with existing businesses and community facilities (such as places of worship. pubs. musi c venues and sports clubs). Existing businesses and facilities should not have unreasonable restrictions placed on them as a result of development permitted after they were established. Where the operation of an existing business or community facility coul d have a significant adverse effect on new development (including changes of use) in its vicinity, the applicant (or 'agent of change') should be required to provide suitable mitigation before the development has been completed." [Emphasis added] 3.3.3. The Agent of Change principle in Paragraph 200 of the NPPF is significant as it enables additional support beyond that provided in the Appeal scheme and justifies a departure from some of the conclusions set out in the Inspector's decision, which is relied on heavily within the Applicant's Planning Statement. 3.3.4. The applicant's Planning Statement only references the Agent of Change principle in relation to London Plan Policy D13. Policy D13 (C) is important in this regard, where it states that: "New noi se and other nuisance -generating development proposed close to residential and other noise -sensitive uses should put in place measures to mitigate and manage any noise impacts for neighbouring residents and businesses." 3.3.5. Paragraph 3.13.2. clearly underlines that whilst new development proposed to existing noise-generating uses should be designed to protect the new occupiers, the same applies in reverse and if an application for noise -generating uses affects noise-sensitive uses, 'the onus is on the n ew use to ensure its building or activity is designed to protect existing users or residents from noise impacts. ' 3.3.6. The Agent of Change Principle, incorporated into national and London planning In any event, the application gives effect to government policy to enable a more equitable distribution of noise around Heathrow and the mitigation proposed exceeds that required by policy. July 2025 London Borough of Hounslow Heathrow responses policy from July 2018 and March 2021, respectively, requires that developers proposing noise-generating uses near sensitive sites ensure adequate mitigation to protect existing residents or businesses. This principle was not part of policy during the earli er appeals but must now be considered in decision making. Its inclusion necessitates revisiting mitigation measures proposed in the S106 agreement, ensuring they reflect the heightened policy requirements. 4. Assessment 4.2. Whilst there is no predicted increase in overall movements, the noise assessment shows that there will be a large amount of sensitive receptors and areas that will be affected by noise associated with aircraft that were previously less or not affected by aircraft noise. This will have significant effect on perception of the noise environment for residents and sensitive users. 4.3 It is important to note that adverse impacts are predicted at additional receptors, including residents of Hounslow and als o schools, community buildings, parks and areas of relative tranquillity and libraries. Whilst the proposals do not lead to an increase in the number of movements at Heathrow Airport, Easterly Alternation will redistribute noise around the airport more equally for the 20 -30% of the time the Airport is operating on easterlies. Using the northern and southern runways more evenly will result in both increases and decreases in aircraft noise. However, the proposals mean that the same communities do not experience all of the noise when the airport is operating in an easterly directio n. Instead, the noise is alternated and shared, with a clear break provided to communities in the form of noise respite. The assessment shows that the communities that will experience the biggest changes are the same communities that will experience noise respite. The airport has tailored its noise mitigation and compensation proposals to target those most affected by the scheme with Appendix 7.5 of the ES includes a list of all non-residential noise sensitive receptors and parks and open spaces which are expected to experience an impact based on the adopted assessment methodologies. 4. Assessment 4.4. We have undertaken a review of the above documents and highlight the following concerns: 4.5. LOAEL Areas Government policy differentiates between aircraft noise impacts which are the point at which adverse effects are observed, where annoyance may become significant at a community level, and where those impacts become 'present and disruptive' and as such noise insulation is required to avoid such effects. These concepts July 2025 London Borough of Hounslow Heathrow responses 4.5.1. The Aviation Policy Framework Section 3 3.17 notes the following: "We will continue to treat the 57dB LAeq 16 hour contour as the average level of daytime aircraft noise marking the approximate onset of significant community annoyance. However, this does not mean that all people within this contour will experience significant adverse effects from aircraft noise. Nor does it mean that no-one outside of this contour will consider themselves annoyed by aircraft noise." 4.5.2. This policy reflects the concern that noise - sensitive receptors outside of the applicant's Significant Observed Adverse Effect Level (SOAEL) would still be subjected to adverse effects (in accordance with the above policy) as a result of aircraft mo vements that they were not previously exposed to. 4.5.3. This includes large areas of West, Central and South Hounslow together with The Thorncliffe Road area. Buildings in these areas will not currently be insulated receive aircraft noise. Some of these areas will receive 20 NR 65 flights where there were previously no NR 65 flights. The QNS eligibility boundary would need to be revised to reflect changes in NR 65 noise levels in accordance with the above policy. underpin aviation and national noise policy and planning practice guidance. 4. Assessment 4.6. Noise Metrics 4.6.1. There are areas (as described above) that will receive maximum noise levels well above 65 dB where they are currently not subjected to aircraft noise. Buildings in these areas will not necessarily be insulated for aircraft noise. 4.6.2. Furthermore, some of these areas, where they are away from busy roads, currently have background noise levels in the evenings of around 40 dB LA90 in the evenings, meaning that there will be an increase in noise levels during overflights of up to 30 dB. These metrics (LAsmax / or SEL) have not been presented in graphical form for properties and sensitive spaces within Hounslow which are expected to experience a significant change in LAsmax levels. The noise assessment considered in the ES applies all relevant Government policy metrics for the assessment of aircraft noise, namely the LAeq,16hr and LAeq,8hr. Secondary metrics in the form of N65 and N60 are also presented. The LAeq,16hr and LAeq,8hr ar e the primary metrics for the assessment of effects and are supported by Government policy and the associated evidence base. There will be locations where LAmax levels will be higher due to EAI. The assessment has not specifically presented these however these are likely to follow the same trends observed for increases in the busy easterly day N65 metric. LAmax levels are not the only component to aircraft noise effects. The number of July 2025 London Borough of Hounslow Heathrow responses 4.6.3. Similarly, only the aircraft noise baseline has been assessed, not the baseline in terms of overall noise levels (L90) or existing numbers of LAsmax events, which means that some properties and sensitive spaces will experience significant changes in noise exposure, but these have not been captured in the assessment or the QNS eligibility. 4.6.4. In accordance with the HLP Policy EC3, these metrics need to be provided. aircraft noise events, their individual levels and their durations are all factors in how annoyed or sleep disturbed an individual or community can be. This is why the LAeq-based metrics best correlate with such effects and have been adopted by Government to underpin aircraft noise assessments and intervention policies such as noise insulation scheme eligibility. 4. Assessment 4.7. Equalities Weighting 4.7.1. The areas where there is an increase in exposure to noise as a result of the proposals, largely fall within Equal Opportunities areas of higher deprivation and incidence of mental health issues. The areas where there is a reduction in exposure to noise as a result of the proposals are largely within Equal Opportunities Areas where there is lower deprivation and incidence of mental health issues. "Environmental noise is one of the leading environmental risks for physical and mental health and well -being, contributing significantly to the burden of disease in the WHO European Region". The Health chapter in the Environmental Statement is not a Health Impact Assessment. It is expected that the SOAEL will need to be weighted to reflect the deprivation and mental health inequalities. See Heathrow response to 4.9.1, 4.9.2 and 4.9.3. 4. Assessment 4.8 Mitigation and Compensation 4.8.2. The Council has been made aware of waiting lists of up to 8 years for house improvements to properties eligible for the QNS scheme. It is considered that eligible properties should be provided with noise insulation measures within a reasonable timeframe, not exceeding two years. The QNS is a much wider scheme and not part of this planning application. The roll out of the QNS will be dependent on funding, supply chain capability and community take up. The scheme is designed to roll out in phases with the order of priority determine d by the Prioritisation Panel comprised of representatives of different stakeholder groups. 4. Assessment 4.8 Mitigation and Compensation The roll out of the QNS will be dependent on funding, supply chain capability and community take up. July 2025 London Borough of Hounslow Heathrow responses 4.8.3. We seek greater clarity and certainty on the delivery of the legacy QNS scheme in the Borough, specifically on how HAL prioritise these properties and how they manage property reviews and maintenance beyond the lifespan of these improvements. The draft Heads of Terms set out proposals for the timing of mitigation directly related to this application. 4. Assessment 4.9. Residential Receptors 4.9.1. Chapter 8 of the NPPF pertains to the promotion of healthy and safe communities. Paragraph 96 outlines that planning decisions should 'enable and support healthy lives, through both promoting good health and preventing ii/ - health, especially where t his would address identified local health and well being needs and reduce health inequalities between the most and least deprived communities. 4.9.2. The proposed development is set to directly impact numerous communities in Hounslow, particularly Heston and Cranford, a community characterised by significant levels of deprivation and financial vulnerability. NHS data indicates that approximately 4,700 residents in Heston and Cranford fall within the most deprived IMO Levels 1 and 2 (4); while the London Borough of Hounslow's Equality Diversity and Inclusion Strategy (5) expands this figure to 13,000 residents under broader definitions of deprivation. 4.9.3. Affordability is a critical concern in this Heston and Cranford, where over 50% of households are in socially or privately rented accommodation, and more than 30% of residents are employed in routine or semi -routine occupations. These economic const raints mean many residents are unlikely to have the financial means to fund necessary mitigation measures, such as enhanced insulation or ventilation, to address increased noise and air pollution resulting from the development. It appears that this relates to the need to consider equalities. It is the duty of the determining Authority to undertake an Equalities Impact Assessment for the proposed development as part of the planning application. All the relevant information has though been provided by the applicant to support this. Please see Appendix 8.1 Equality Statement of t he Environmental Statement. The Environmental Statement, Volume II Chapter 9: Public Health assessment makes specific reference to people with existing poor health (including long -term health conditions) and to autism in reaching its conclusions. Environmental Statement, Volume II Ch apter 9: Public Health section 9.7 specifically considers how the project’s noise effects would be distributed in relation to vulnerable groups, including in Hounslow. It is considered that NPPF paragraph 96 requirements are appropriately taken into account and the effect of the project in providing a more equitable distribution of noise exposures is consistent with that national policy position. Environmental Statement, Volume II Chapter 9 sets out detailed study areas (Health Site -Specific Study Areas (HSSSAs)) so that the redistribution of noise effects can be understood across the surrounding population. This includes considering areas of depri vation, which are set out in Environmental Statement, Volume III Appendix 9.2 Public Health Figures 9.9 and 9.10. These shows that with regard to deprivation in general, and health deprivation in particular, there is a relatively even distribution between the beneficial and adverse effects. As noted in July 2025 London Borough of Hounslow Heathrow responses 4.9.4. The health profile of this community further underscores the need for careful consideration. Residents in these areas experience disproportionately high rates of long -term health conditions, and children with autism - a prevalent condition in this c ommunity - are particularly vulnerable to sensory challenges exacerbated by noise pollution. Without robust mitigation measures, including 100% compensation for house repairs and other necessary improvements, this development risks worsening health inequalities and diminishing the quality of life for an already underserved population. 4.9.5. Figure 1 underlines the health inequalities in the immediate area, demonstrating that the proposed changes will inordinately impact the most deprived communities around the airport. In accordance with this, Paragraph 96 should be considered, and further mitigation should be made available to overcome the existing inequalities towards the east of the airport when compared to the wider area receiving relief on account of this application. Chapter 9 paragraph 9.7.104 HSSSA 1 (the main area of adverse effect|) has a lower proportion of households that are not deprived (34.9%) compared to HSSSA 4 (44.2%), the main area of beneficial effects. It also notes that the population in HSSSA4 (area of beneficial effect) is larger at 93,000 people compared to the main area of adverse effect HSSSA1 (a population of 58,000), and that the proportion of people who are disabled under the Equality Act is slightly higher in HSSSA 4 (13.5%) than in HSSSA 1 (11.8%). Further detailed analysis and discussion around the relative vulnerability of the areas of affect are set out in Chapter 9 and its appendices. It is important to a balanced conclusion that both the beneficial and adverse effects are considered together, not just the adverse effects in isolation. Mitigation includes the Longford Noise Barrier, QNS extension and the Easterly Alternation Noise Mitigation Package, the latter including residential, open space and school measures. Mitigation is further discussed in Environmental Statement, Volume II Chapter 7: Noise and Vibration. 4. Assessment 4.9. Residential Receptors 4.9.6. It is considered that the mitigation proposed under the easterly alternation mitigation scheme is unsuitable when considering the likely costs of mitigation in each affected home and the demographics of those homes affected. Funding allocations must reflect this disparity to ensure equity. 4.9.7. It is unreasonable for HAL to place The mitigation proposed is reflective of existing policy and comparable with other airport schemes. The monies available can be used to prioritise the most sensitive rooms in a household, should the resident be unable or not want to contribute to additional works. July 2025 London Borough of Hounslow Heathrow responses additional financial burdens on affected homes, or placing the expectation on landlords to deliver these improvements for their tenants. Further detail is required to understand how the mitigations proposals were calculated and whether recipients would therefore be expected to contribute towards sound insulation. 4.9.8. We would expect HAL to identify the likely scope of impacted residents, and under the Agent of Change principle, ensure that the affected homes are improved to the requisite standards to maintain the internal noise standards experienced currently. This will help ensure that the proposed development does not further entrench inequalities or undermine the health and well - being of Hounslow residents. 4.9. Residential Receptors 4.9.9. We also have concerns that the noise metrics used to identify the properties entitled to compensation and mitigation under the easterly alternation mitigation scheme and require further information before commenting on the areas affected, as set out in Section 5. The noise mitigation and compensation proposals are set out comprehensively in Section 7.7 of the ES. The mitigation proposals are based on current and emerging Government policy thresholds. 4.10. Non-Residential Receptors 4.10.1. Consistent exposure to high levels of noise from aircraft has been linked to well being in children. The World Health Organization has highlighted that excessive noise can significantly impact learning and cognitive performance, especially in children. There has been no consideration of early years sensitive receptors. Early years provision often provide for infants and young children to be able to sleep during the daytime. Schools within the areas where there will be an increase in the number of schools experiencing disturbing levels of LAsmax levels during school time (particularly du ring the summer, when windows are open) but are not within the assessment, QNS or easterly alternation mitigation scheme eligibility. Similarly, other learning areas, such as community buildings, libraries and study areas should also be included. Environmental Statement, Volume II Chapter 9: Public Health paragraph 9.2.5 confirms that regard has been given to World Health Organization noise guidelines. Children are specifically considered as a high sensitivity group throughout Chapter 9. Cognitive performance is included in the effect pathways for noise effects discussed in Chapter 9 (paragraph 9.7.2 for construction and paragraph 9.7.204 for operation). Environmental Statement, Volume II Chapter 7: Noise and Vibration and Chapter 9: Public Health both include specific discussion of nurseries, schools, libraries and community buildings. For example, Chapter 9 section 9.7 has sections on Community Infrastru cture Public Health Implications for both construction and operation. Chapter 9 section 9.7 also has a specific section on Educational Attainment Public Health July 2025 London Borough of Hounslow Heathrow responses Implications during operation, recognising the importance of development and learning environments for public health. Mitigation includes the Longford Noise Barrier, QNS extension and the Easterly Alternation Noise Mitigation Package, the latter including residential, open space and school measures is discussed in Environmental Statement, Volume II Chapter 7: Noise and Vi bration. 4.10. Non-Residential Receptors 4.10.2. The area proposed is an area of high level of deprivation with existing challenges in accessing key services, healthy food, and employment. Beyond churches, GP practices, pharmacies, business, high streets, and the general area should be considered to minimise negative impact on income. The application has not duly considered the likely impact on community life or identified mitigation measures to maintain their role in economic opportunity, social interaction, and wellbeing. 4.10.3. The application should explicitly address the potential public health implications of increased noise exposure on mental health, stress, and sleep disturbance. Community buildings play a key role in mitigating these effects and should therefore receive adequate support. Environmental Statement, Volume II Chapter 9: Public Health assessment Section 9.6 discusses the scope of the assessment. Chapter 9 Table 9.22 presents elements scoped out in the Scoping Report (and as such agreed as scoped out by LBH in their Scoping Opinion). This includes effects on ‘diet and nutrition’, ‘transport modes, access and connections’ and ‘employment and income’. Agreement to scope these matters out reflects that they are not considered to give rise to likely significant effects as a result o f the Proposed Scheme. As such, the noise exposures associated with the project changes are not considered to have the potential for significant public health effects associated with accessing key services, healthy food, and employment. In reaching this conclusion it is relevant to note that effects are limited to around 10% of the time during the summer, and around 14% over the course of a year, with no change in the ATM cap at Heathrow as part of the Proposed Development. The Environmental Statement, Volume II Chapter 9: Public Health assessment section 9.7 specifically assesses the potential public health implications of increased noise exposure on mental health, stress, and sleep disturbance. The redistribution of noise e ffects has been assessed in in relation to effects on people, on use of outdoor space, on use of community infrastructure and on educational attainment. This includes July 2025 London Borough of Hounslow Heathrow responses consideration of effects relating to community buildings associated with vulnerable populations. 4.10. Non-Residential Receptors 4.10.4. We would expect that the mitigation measures are expanded to ensure that community and education buildings in the affected areas will be assessed once the proposal is delivered to ensure that the building is meeting current standards. 4.10.5. The list of affected community assets eligible for the QNS scheme does not include Meadowbank Adult Education Centre and Cranford Library. They should both benefit from enhanced mitigation under the easterly alternation mitigation scheme as they se rve vulnerable populations, including low-income families, elderly residents, and those with limited mobility. These groups are less able to adapt to the increased noise exposure. Excluding these facilities from mitigation measures would significantly aff ect the wellbeing of these populations. No properties are excluded from the mitigation proposals where they meet the qualifying criteria. We would be pleased to discuss these properties further with Hounslow. 4.11. Parks 4.11.1. Particulate emissions in the form of dust, which come from increased road traffic, - aircraft engine emissions, - emissions from airport motor vehicles and - emissions from other sources (e.g. heating/power plants incinerators and construction activities) can have an impact on air quality in the vicinity of the airports. It is found that at sites as far as 7km from the airport, the particle number size average particle number size (PNCs) was 2 and 1.33 -fold higher, respectively, when winds were from the direction of the airport. 4.11.2. The physical and chemical properties of particulates can have an impact on human health, while they are using gym facilities, walking in the green spaces in Hounslow. 4.11.3. Construction dust can also settle on vegetation in the green spaces and in the gardens in Hounslow, affecting plant growth and ecosystem health. Several mitigation strategies can be implemented which focus on reducing the release of pollutants and adopting sustainable Concentrations of PM10 and PM2.5 are presented in the ES, including in the form of contour plots covering parks in Hounslow. In terms of air quality, easterly alternation will have little effect in Hounslow as Hounslow lies downwind of the airport during e asterly operations. Construction dust will only arise at a considerable distance from Hounslow and will not reach the Borough. Construction activities will be managed through a CEMP to minimise dust generation. July 2025 London Borough of Hounslow Heathrow responses approaches throughout the construction stage and operation of the airport include: • Dust Control Measures • Emission Reduction Technologies • Alternative Fuel and Energy Sources • Use of Low VOC Materials • Sustainable Transportation Strategies • Implementing Best Practices and Guidelines • Education and Training to the construction workers the importance of air pollution mitigation and proper handling of materials can promote awareness and responsible practices. 4.11. Parks 4.11.4. Noise pollution will affect the open spaces for recreational activities and adverse effect can be seen in the east; with 3,100 residential properties in Hounslow, Cranford, Harlington, Wraysbury (with an increase of 1dB above SOAEL). 4.11.5. It can cause community annoyance, disrupt sleep, adversely affect academic performance of children, and could increase the risk for cardiovascular disease of people living in the vicinity of airports and more so while using the open spaces. 4.11.6. The majority of adverse impacts for non - residential receptors are identified within North Feltham, Heston, and greenspace on Avenue Park, Waye Avenue and Firs Drive Open Space. 4.11. 7. A number of Hounslow parks and open spaces, notably Avenue Park, Waye Avenue and Firs Drive are anticipated to experience a noise increase during easterly operations. The increased level of noise has the potential to reduce the extent to which these areas are regularly used by residents for physical and recreational activities, therefore local parks will be affected by the proposed development for a meaningful period of the day (3pm onwards - when school children and families are likely to visit parks and green spaces). This could lead to reduced social interaction and social support more so for disabled people and people with special needs. 4.11.8. Compensation is proposed to provide enhancements to these public open spaces, The 3,100 residential properties referred to will be eligible for the full cost of insulation under the QNS which will avoid significant adverse effects on health and quality of life for these receptors. Avenue Park is identified in the ES as experiencing an adverse likely significant effect and will be eligible for a share of the £250,000 compensation as identified in the draft Heads of Terms. Waye Avenue and Firs Drive are not identified as experiencing adverse likely significant effects in the ES. Both parks experience a n increase of between 1 to 2dB in summer average L Aeq,16hr with the Proposed Development and are therefore not identified as experiencing a likely significant effect following the methodology outlined in Table 7.24 in the ES. The two parks currently routinely experience aircraft noise during westerly operations a nd therefore the increase in noise during easterly operations (whic h would be at its largest during 09L departures which would occur only 10 - 14% of the time) would not be expected to reduce the extent to which these areas are regularly used by residents for physical and recreational activities. The use of the funds for Avenue Park proposed by LB Hounslow is noted. It would be for the local authorities to determine how best these funds are used, but Heathrow would wish to be assured that the funds would be used for park July 2025 London Borough of Hounslow Heathrow responses through adaptation, giving alternative interest and facilities that would promote their use and seek to mitigate. The proposed funds to be made available to the Hounslow with respect to compensation would consider: • Increased canopy cover • Green noise barriers {acoustic engineering) • Bioremediation (pollutant absorbing plants and fauna) • Tree lined pathways • Recreational and fitness facilities • Welcoming entrances • Pathway/infrastructural improvements and remodelling/regrading 4.11.9. The proposed compensation of £250,000 to cover the three identified parks is not sufficient, and a compensation of £500,000 for the London Borough of Hounslow is requested for park and environmental improvements. 4.11.10. In addition to the contribution to Council owned parks, further contributions to community greenspaces should also be considered, specifically smaller spaces near housing estates where children play. A programme for incentivising play in affected areas should be incorporated as part of the mitigation package. enhancements and delivered within a reasonable timescale. It is not agreed that the proposed compensation is not significant, or that further contributions to community greenspaces should be considered. There is no policy obligation on Heathrow to provide compensation to Avenue Park, and it was not a feature of the financial package which was found acceptable by the Inspector and Secretary of State in the decision to approve in 2017. It is promoted as a p roportionate payment in the expectation that the Borough Council will be able to identify worthwhile projects and initiatives for the park to enhance the experience of park users to compensate for the effects of easterly alternation, which will be experien ced by park users for a limited period of time. The nature of easterly alternation is such that periods of easterly operations and alternation during an easterly day will be publicised on Heathrow's website and known in advance. These effects will be predicable. Park users could choose to time their visits to avoid the effects if they wish. 4.12. Long term monitoring and availability of compensation 4.12.1. We have concerns that the noise impacts identified in the EIA may not fully reflect the real - life experience once the development is built out. 4.12.2. The proposal will have long -term and continuous effects on the London Borough of Hounslow, requiring sustained oversight and mitigation. We recommend Heathrow engages directly with Cranford's community to identify specific concerns. Establishing a liaison group with representatives from schools, community buildings, and residents will ensure local priorities are considered and addressed. The QNS boundary will be regularly updated to reflect changes in noise exposure to ensure all eligible properties are identified. Long term monitoring of operations and noise impact will continue as part of Heathrow's ongoing NAP process. 4.12. Long term monitoring and availability of compensation There is already a widespread monitoring network, supported by mobile monitors and regular modelling. This will inform how July 2025 London Borough of Hounslow Heathrow responses 4.12.3. HAL should implement a clear monitoring framework to evaluate the effectiveness of both mitigation schemes, with regular monitoring, reporting and opportunities for community feedback. This ensures ongoing accountability and transparency. 4.12.4. Each Council should be provided an annual monitoring fee to maintain air quality and noise quality monitoring withing affected areas. This should be secured to ensure continuous assessment of real-life noise impacts. 4.12.5. The S106 should include additional triggers for a review of the mitigations 2, 5 and 10 years after the proposal is completed to enable monitoring of actual noise levels and other environmental impacts, ensuring they align with predictions. 4.12.6. In accordance with above, the proposed compensation and mitigation should remain available beyond the 2028 deadline, recognising that many affected residents may not undertake mitigation works until the full impact of the proposal is realised. 4.12. 7. Furthermore, the proposed noise insulation measures for residential and non - residential buildings will likely require maintenance or replacement after 30 years. Heathrow Airport should commit to funding replacement insulation at the end of its lifecycle to maintain effective noise mitigation long-term. 4.12.8. All mitigation measures, including the easterly alternation mitigation scheme, should be accessible indefinitely while flights over Cranford continue to operate, ensuring long-term protection for affected communities. the QNS boundary evolves over time. The mitigation installed is c hecked by a qualified surveyor and a % of residents re- surveyed after installation. Section 5. Further Technical Information Required 5.1 Hounslow requires further information before making a formal response on the application. The requests are made with reference to the policy and general concerns listed above. 5.2. LOAEL Areas & Noise Metrics a. Please provide a noise level contour plot for all Areas of Hounslow in terms of 16 hr LAeq. The ES provides a significant volume of information describing the noise impacts of the proposals utilising a range of metrics and sensitivity tests. The assessment has utilised metrics underpinning Government and metrics which can be used to help articulate impacts, such as the 'busy easterly day N65' metric. Average LASmax levels have been used to inform impacts on sleep through a sensitivity test July 2025 London Borough of Hounslow Heathrow responses b. Please provide a noise level contour plot for all Areas of Hounslow in terms of 8 hr LAeq. c. Please provide a noise level contour plot for all Areas of Hounslow in terms of N65. d. Please provide a noise level contour plot for all Areas of Hounslow in terms of LAsmax. e. Please provide a noise level change (with minus without) contour plot for all Areas of Hounslow in terms of 16 hr LAeq. f. Please provide a noise level change (with minus without) contour plot for all Areas of Hounslow in terms of 8 hr LAeq. g. Please provide a noise level change (with minus without) contour plot for all Areas of Hounslow in terms of N65. h. Please provide a noise level change (with minus without) contour plot for all Areas of Hounslow in terms of LAsmax a. It should be noted that the models are already created for the above equests so it should simply be a case of re -outputting the results in more detail. We also request the above to be in digital format (dxf etc) so that we can import into our own noise modelling. i. Pl ease provide an assessment of change in LAsmax levels relative to baseline LAsmax levels, Baseline LAeq and L90 levels in the Hounslow area. This assessment should focus on areas and sensitive receptors that currently receive low levels of aircraft noise a nd also areas that currently have low levels of transport and other background noise. The assessment should include specific property examples together with consideration of different uses and noise insulation properties of different building types (both r oofs and glazing) and different levels of deprivation. It is expected that a minimum of 50 property and receptor examples should be suggested to Hounslow for approval and then assessed. It is expected that baseline noise levels can be mostly obtained from available public data (within the last 5 years), however a small amount of noise measurements may need to be made. In the event of noise measurements being required, 24 hr, major parameter 15 minute intervals (LAeq, LAmax, Lmin ,L90, L 10) should suffice. considering 'objective awakenings'. All figures provided in Volume 4.7.5 include the boundaries of the London boroughs, including Hounslow. This is supported by Community Focus Areas in Appendix 7.8 which set out local specific impacts and eligibility to H eathrow's various existing and proposed schemes. With reference to 5.2i, this information is not necessary as 15 -minute metrics cannot be correlated to aircraft noise impacts or effects. Section 5. Further Technical Information Required 5.3 Early Years Sleep Disturbance and Learning & Libraries/ Study Spaces. a. Please provide an extended assessment The submitted assessment is robust and comprehensive with the assessment taking into account relevant guidance for receptors where changes in aircraft noise may be significant. July 2025 London Borough of Hounslow Heathrow responses including all schools and early years provision within Hounslow. This should include indicative changes in internal noise levels (LAsmax, N65 and LAeq) consideration of roof/glazing and ventilation at worst affected learning facades (with reference to B893 - Acoustic Design of Schools) and inclusive of community buildings, libraries and study areas. Please revise the QNS eligibility in light of these assessments. Section 5. Further Technical Information Required 5.4. Proposed Mitigation Scheme a. Please provide a Health Impact Assessment. This should include consideration and SOAEL and NOAEL weightings for the deprived areas and areas with poor mental health. Please revise the overall assessment results and QNS and Easterly Alternation Mitigation Scheme eligibility in light of these additional assessments. b. Please revise the QNS and eligibility of the easterly alternation scheme in light of the above assessments. Mitigation, for a range of environmental aspects, is detailed within the planning application in particular within the Environmental Statement and associated documents. A Health Impact Assessment has been undertaken and is documented as Chapter 9 of the Environmental Statement. This meets the requirements of the EIA Regulations (2017) which now require health to be considered within the EIA process as opposed to being part of a standalone process. The Health assessment provided as part of the ES takes full account of the noise assessment and the QNS, which is considered to be fully appropriate. Section 5. Further Technical Information Required 5.4. Proposed Mitigation Scheme c. Please provide justification for the proposed contributions under the QNS and Easterly Alternation Mitigation Schemes. This should include an analysis of the likely affected properties, cost estimates for noise mitigation in these buildings and further information on the likely expectations on property owners to secure long-term mitigation on these properties. Full details of the QNS Residential Insulation Scheme are provided in Section 4 of Appendix 17.2 of the ES. That section notes that each property will be independently assessed to determine the insulation measures that will be most effective, noting that the scheme will incorporate some or all of the following: - The supply and installation of replacement primary windows or secondary glazing and external doors. - The supply and installation of acoustically attenuated ventilation in eligible rooms. July 2025 London Borough of Hounslow Heathrow responses - The Installation of an acoustic quilt within the roof void. - Upgrading of ceilings within eligible rooms where practicable to provide an increased level of acoustic attenuation. The scale of expenditure per property is set out in Heathrow’s Noise Action Plan and scrutinised through that process. For the majority of eligible properties, the limit of £34,000 will be sufficient to provide the full cost of insulation for all eligible rooms. To date the average spend per property has been between approximately £11,000 and £18,000 depending on area and property type. This cost covers the survey and inspection work required, scaffolding, new acoustically specified windows and doors, ventilation system, loft insulation and ceiling overboarding where required. Should the expenditure required go beyond the limit of £34,000, this will be referred to Heathrow’s Prioritisation Panel as a special case for determination. The limit of £34,000 per dwelling is adjusted for inflation and subject to periodic review and uplift by Heathrow. Where the dwelling has already been treated with acoustic glazing (double or secondary) or ventilation, Heathrow’s assessors will determine whether it remains effective or requires replacement under the scheme. For the levels of cost offered additionally for easterly operations, where properties do not qualify for QNS, these have been determined as follows. Properties eligible for the £3,000 scheme are exposed to between 54-60dBLAeq,16h and would be likely to meet internal July 2025 London Borough of Hounslow Heathrow responses criteria from BS8233 with standard glazing (i.e. existing glass retained but double-glazed unit), loft insulation and enhanced ventilation. This is in line with a £3,000 contribution which could cover, for example, surveys and installation of a ventilation product and 50m2 loft insulation. Properties eligible for the £12,000 scheme are exposed to between 60- 63dBLAeq,16h and would be expected to meet internal criteria from BS8233 with replacement windows, loft insulation and enhanced ventilation. This is in line with a £12,000 contribution which could cover, for example, surveys and installation of a ventilation product, bathroom/kitchen ventilation, 50m2 of loft insulation and up to 8 units of secondary glazing. As these contributions are therefore in line with the typical costs required to meet the internal criteria of BS8233, the level of contribution is proportionate to the noise impacts for these noise exposures below SOAEL. Section 5. Further Technical Information Required 5.5. We would also like to meet with HAL and Hillingdon Council to understand the funding and delivery of compensation and mitigation packages proposed as part of the S106, including the specification of any insulation schemes in the Borough. We are grateful for the meeting held in May and hope that the additional responses provided here are helpful. 6. Summary 6.1 Hounslow Council remains open to engaging further with HAL to ensure appropriate mitigation measures are secured. However, at present, insufficient information has been provided to demonstrate that the proposal will not result in significant harm to Hounslow residents. 6.2. Before a formal position can be reached, Hounslow expects HAL to: July 2025 London Borough of Hounslow Heathrow responses • Strengthen Mitigation for Deprived Communities: The cumulative impact of noise exposure must be properly addressed, with targeted mitigation for the most affected areas in line with NPPF Paragraph 96. • Expand the Scope of Compensation: The mitigation package should ensure full insulation coverage for all affected properties, including social housing and private rentals, without placing a financial burden on residents or landlords. • Protect Community Assets: Schools, libraries, and other community facilities must be included in the mitigation strategy, with funding allocated for noise insulation and adaptive measures. • Commit to Long -Term Monitoring & Compensation: Mitigation should not be time - limited-it must be available beyond 2028 to ensure ongoing protection for affected residents. 6.3. Hounslow urges HAL to engage further with the Council and affected communities to refine its mitigation proposals and demonstrate a commitment to protecting the health and well - being of our residents. Until these issues are addressed, we cannot provide full support for the current proposals.

HEATHROW’S SUMMARY RESPONSE 1. The effects of easterly alternation The application responds to government policy which calls on Heathrow to submit proposals for easterly alternation in order to: - facilitate the redistribution of noise more fairly around the Airport; and - extend the benefits of respite during runway alternation to all communities around Heathrow. In reaching its policy decisions to end the Cranford Agreement the Government recognised that there would be some adverse effects but, in addition to bringing greater fairness in how aircraft noise is distributed during easterly operations and in predictable aircraft noise respite, the government decided that it would be preferable to benefit large numbers of people by removing them from the 57 dBA Leq contour, at the expense of exposing a smaller number of people to increased noise at higher levels. The same conclusion was reached by the Secretary of State in the appeal decision in 2017 who found that the application would “implement Government policy to redistribute noise more fairly around the airport; and that the public interest benefits that would result from the development (with appropriate mitigation) should carry very substantial weight in favour of the scheme.” The effect of easterly alternation is comprehensively assessed in the application against all up to date policy and evidence, and it confirms not only would respite be more fairly extended – particularly to communities that have experienced constant overflying without relief since the 1950s – but that the net effects would be undeniably beneficial. The headline noise effects are that easterly alternation would: • reduce the overall number of people exposed above the daytime LOAEL by around 2,800; • reduce the number of people exposed to levels above 54 dB LAeq,16hr (“the approximate onset of significant community annoyance”) by 15,300; • reduce the overall number of people exposed between the daytime LOAEL and SOAEL by 3,900.1 The adverse effects are smaller. Easterly alternation would: • increase the overall number of people within the daytime SOAEL by around 1,100; and • increase the overall number of people exposed to levels above 69 dB LAeq,16hr by around 500. For those people, mitigation would be provided (see further below). The overall effects can be measured in a number of ways, but each approach demonstrates the significant overall benefit of alternation. For example, the submitted EIA shows that: 1 LOAEL is the lowest observed adverse effect level and is recognised as being 51dB during the daytime. SOAEL is the significant observed adverse effect level and is recognised as being 63DB during the daytime. Appendix 6 Overflights: The effect of the Proposed Development is to significantly reduce the population exposed to higher levels of overflights (more than 400, 500 and 600 events during a busy easterly day) as overflights would no longer be as concentrated over specific communities. There would be an increase for communities currently affected by lower frequencies of overflying but a reduction for those affected by much higher levels. This demonstrates the more equitable distribution of flights made possible by easterly alternation. At night: the effect of the Proposed Development in 2028 would be to: • reduce the number of people exposed between the night-time LOAEL and SOAEL by 9,700; and • increase the number of people within the night-time SOAEL by around 1,700. Numerically: • 62,200 people would experience a beneficial change in aircraft noise exposure of at least 1dB; • 39,600 people would experience an adverse change in aircraft noise exposure of at least 1dB. Annoyance and sleep disturbance: • The number of people defined as highly annoyed would reduce by between 400 and 8,200 (depending on the method of calculation). • The number of people living with noise above 54DB, which is defined as the onset of significant community annoyance, would be reduced by 15,300. • the number of people sleep disturbed is forecast to reduce by between 600 and 1,800. These are very significant net benefits that would be brought to thousands of people. The EIA endorses the Government’s assessment that the overall effect of easterly alternation is substantially beneficial. 2. Mitigating adverse effects Heathrow is a designated airport where Government policy is that it “is appropriate for the Government to take decisions on the right balance between noise controls and economic benefits, reconciling the local and national strategic interests.” National policy sets the requirements for airport mitigation. That policy has not significantly changed since the 2017 decision with the Government expecting airport operators to offer financial assistance towards acoustic insulation to residential properties which leaves them exposed to levels of noise of 63 dB LAeq,16hr, or more. Heathrow’s quieter Neighbourhood Support scheme (QNS) goes much further and offers full noise insulation up to an indexed cap of £34,000 (now £35,130) for all residential properties affected by aircraft noise at 63 dB LAeq,16hr and above. It also makes eligible residential properties exposed to night-time noise at 55 dB LAeq,16hr and above, and properties specifically affected by noise from arriving aircraft at night. The QNS also offers similar mitigation to non-residential properties such as schools.2 The QNS was consulted on and endorsed by Government as part of Heathrow’s Noise Action Plan in 2024. It can be regarded as up to date. Any properties where noise levels reach 63dB LAeq,16hr as a result of easterly alternation would qualify for the QNS, just like any other property around the airport. In the 2017 Cranford Inspector’s report, the Inspector made clear that it would not be proportionate or reasonable to expect Heathrow to amend its airport wide noise insulation scheme as a result of the Cranford application. Neither would it be fair for residents affected by noise from easterly alternation to be compensated / mitigated to a higher standard than others already affected by aircraft noise. Hence the fair thing to do is to offer noise insulation to those uniquely affected by clearly noticeable adverse effects from changes in aircraft noise. The overall changes in noise effects are relatively small and easterly alternat ion does not significantly affect the general shape of the QNS boundary. For example, residents of Longford already qualify for QNS. One area is identified as being likely to experience a greater level of change than others. This area runs up from Cranford to North Hyde and Southall in Ealing. Here the area will be overflown by departures on a designated flightpath that is currently rarely used (as a result of the Cranford Agreement). The area is not directly in line with the runway, so it is not affected by arrivals. The flightpath would be used routinely for departures during easterly alternation , and the area would be subject to a change in daytime noise exposure levels of up to 3 to 5.9 decibels, although overall noise levels would remain below 63dB LAeq,16hr. 2 Where the full cost of noise insulation unusually exceeds £35,130 Heathrow approaches this on a case- by-case basis. Cases can be referred to the independent Prioritisation Panel and to date Heathrow has accepted all of its recommendations. The QNS is indexed annually. Area north-east of Cranford, newly affected by easterly departures (figure 1) As a result of that area not being currently overflown, the change in noise levels is more significant. However, flying there would only take place during easterly operations and only then for 50% of the time due to alternation, i.e. for the 50% of the day when the northern runway is used. In any year, the area would be overflown and affected 10% to 14% of the time on average, meaning that, following the introduction of easterly alternation, the summer or year round noise levels would not reach a level normally defined as significant adverse and the properties would not qualify for QNS, because the noise levels would be much lower. Whilst there is no policy obligation to do so, Heathrow does recognise that easterly alternation will bring some new effects. Accordingly, for the purposes of this application (and subject to planning permission being granted and implemented), in addition to the QNS scheme, Heathrow has devised the Easterly Alternation Noise Mitigation Scheme, which responds to changes in noise levels, even where those changes do not result in overall levels which would normally qualify for noise insulation under government policy or the QNS. The table below shows the Easterly Alternation Mitigation Scheme that was set out in the application. Figure 1 above shows where the QNS and this additional mitigation will apply. Heathrow have provided officers with details of how the cost of the noise insulation works would be funded and that, whilst the cost and recommended insulation solutions will vary from property to property, the funding is likely to be sufficient to meet Heathrow's internal noise level targets, which are aligned with British Standard BS8233:2014 (which strictly only apply to new homes). 3. Further discussions with LB Hillingdon (shared without prejudice) Officers have sought clarity on the justification for the detail of the mitigation proposals, including in the light of proposals that have been put forward by those promoting expansion at Luton and Gatwick Airports. In response to the questions raised, Heathrow’s response is set out below. LBH: above 63dB Heathrow’s QNS scheme appears to be capped at £34,000 whilst Luton and Gatwick’s schemes are uncapped. Heathrow: the QNS figure of £34,000 is not capped in practice, because: - first, it is indexed to keep pace with inflation – it is currently published as £35,130 and will continue to be indexed; - experience to date is that full noise insulation can be provided to properties at costs ranging between £11,000 and £22,000. This is particularly meaningful because Heathrow’s QNS roll out has prioritised areas at Longford and Stanwell Moor where noise levels are relatively high. As the QNS is rolled out to areas with lower exposure, it is likely that average costs to achieve suitable insulation may be lower. - As we have explained in our responses to LBH’s detailed questions on noise insulation installation, in exceptional cases (such as unusually large premises), Heathrow has reached agreement on a case-by-case basis to meet higher costs where that is necessary; and - where disputes and special cases arise, matters are referred to Heathrow’s independent Prioritisation Panel. In all cases to date, Heathrow has accepted the recommendations of the Panel. Heathrow cannot change the terms of its airport-wide QNS, which was endorsed under the Noise Action Plan, but as explained above, the QNS is not capped in practice. LBH: between 60dB and 63dB LAeq,16hr (where there is a 3dB increase), Heathrow is offering £12,000, but Luton offer up to £20,000. How can LBH know that Heathrow’s offer is sufficient? Heathrow: we have studied the noise insulation schemes proposed at Gatwick and Luton and the evidence submitted to support them. We have found no explanation for the £20,000 figure. Heathrow’s figure of £12,000 was broken down and explained in our Response to LB Hillingdon Noise Mitigation Questions, 25 August 2025 (Question 2), as follows: With £12,000: We anticipate that properties 60-63dB will require windows to be replaced to meet BS8233:2014 internal average ambient noise levels, as well as loft insulation and a Siegenia vent or PIV. • Contractor surveys – £500 • Ventilation Product – £1,300 • Bathroom / Kitchen Ventilation – £1,500 • Loft Insulation (50 SQM Average Property size) – £1,500 • Secondary Glazing (8 No. secondary glazing units between 3 & 4 Sqm) – £7,200 Total: £12,000 (EX VAT) As per the above, we are confident that the measures proposed (namely secondary glazing, new ventilation and loft insulation) will meet the required internal ambient noise levels. Again, we have supporting evidence (contractor final accounts to suggest that the £12,000 figure can provide the necessary measures outlined). Having reviewed LB Hillingdon’s question, Heathrow is willing to additionally commit: - that an objective test be set for the sufficiency of mitigation – namely that it should aim to achieve forecast internal noise levels consistent with BS8233:2014 (residential standards for new buildings), or a minimum improvement of 5dB in sound insulation, noting that this target may not be able to be achieved in certain specific circumstances due to the limitations of the existing building fabric/structure. The level of mitigation and relevant works required to achieve acoustic aims set out above will be determined following a surveyor/assessor visiting the property. (Whilst we have set out our confidence that the offer will be sufficient for these purposes, we recognise that LBH seeks greater comfort that a satisfactory environment will be achieved); and - that the role of the Prioritisation Panel is extended to deal with any disputes or referrals under this category. LBH: similar questions arise in relation to Heathrow’s offer of £3,000 for properties in the 54dB to 60dB LAeq,16hr category (where there is a 3dB increase) – why is that sufficient when Luton offers £4,000 to £6,000 and Gatwick offers £4,500 to £6,500? Again, we have found no basis for the offers at other airports. Those airports, of course, do not currently offer any mitigation at these noise levels and have offered to do so only if their airports receive consent for significant expansion. They also both made the point in evidence that their offers far exceed what is required by policy. At Heathrow, easterly alternation brings no growth in traffic. Our proposal was explained in our August Response to Noise Mitigation Questions, as follows: With £3,000: We anticipate that properties between 54-60 dB LAeq,16hr should be able to meet BS 8233 internal average ambient noise levels in habitable rooms with standard glazing (assumes existing glass retained and is double-glazed unit), loft insulation and an enhanced Siegenia vent or PIV. Total cost estimate of PIV and loft insulation: • Contractor surveys – £200 • Ventilation Product – £1,300 • Loft Insulation including hatch and perimeter seal (50 SQM Average Property size) – £1500 Total: £3,000 (EX VAT) We are confident that the measures proposed (namely new ventilation and loft insulation) will meet the required internal ambient noise levels. We have supporting evidence (contractor final accounts) to suggest that the £3,000 figure can provide the necessary measures outlined. At these levels of noise, no planning policy requires noise insulation to be offered. At Heathrow, adverse effects from aircraft noise will only arise approximately 15% of the time for these properties – whereas the cases at Luton and Gatwick relate to effects experienced every day. Accordingly, we regard this offer of compensation for those affected to be a good offer which recognises the change that will be brought about for these properties for only c.15% of the time and a fair contribution to additional insulation if they wish to take up the offer. This is not something, therefore, that would be referred to the Prioritisation Panel and Heathrow does not propose to change this element of its offer. 4. Conclusion The analysis undertaken for this application shows the pattern of effects to be comparable in principle to that understood by the Government when the decision was made to end the Cranford Agreement. Ending the Agreement and introducing easterly alternation brings respite to communities who have been denied it by the Agreement for c.70 years. It benefits significantly more people than it harms. And those who are most affected will have those effects mitigated through a scheme of noise insulation which both exceeds that which the Secretaries of State found to be acceptable in 2017 and exceeds what is required by Government policy. In addition to noise insulation, and recognising impacts on Longford Village, the proposals also include the construction of an up to 7m high purpose-built noise barrier, which responds to consultation responses from residents. The noise barrier will mitigate noise from aircraft on the ground and as they taxi to and use the northern runway for departures. The proposals also provide for a financial contribution to the Council of up to £250,000 (in total) towards the enhancement of Berkeley Meadows, Avenue Park and Cranford Park recognising the adverse impacts identified on these receptors.

Hillingdon Planning Committee – 16th December 2025 PART 1 – Members, Public & Press Report of the Head of Development Management and Building Control Committee Report Case Officer: Sally Robbins 32265/APP/2025/280 Date Application Valid: 20.02.2025 Statutory / Agreed Determination Deadline: 23.12.2025 Application Type: Full Ward: Northwood Applicant: Ms and Mr Jones Site Address: 78 High Street, Northwood Proposal: Demolition of existing rear workshop buildings (Use Class E) and construction of 2 no. self- contained flats and 1 no. dwellinghouse (Use Class C3) with associated private amenity space, landscaping, cycle and refuse storage, together with alterations and a two-storey rear extension to the existing building, including internal layout changes to the first -floor residential flat above the retail unit and the installation of a rear dormer window Summary of Recommendation: GRANT planning permission subject to conditions Reason Reported to Committee: Required under Part 3 of the Planning Scheme of Delegation (Petition received) Hillingdon Planning Committee – 16th December 2025 PART 1 – Members, Public & Press Summary of Recommendation: GRANT planning permission subject to the conditions set out in Appendix 1. 1 Executive Summary 1.1 The application seeks full planning permi ssion for the demolition of the existing rear workshop buildings (Use Class E) and the construction of three new residential units (Use Class C3) with associated private amenity space, landscaping, and cycle and refuse storage, together with alterations and a two- storey rear extension to the existing build ing at 78 High Street, including internal layout changes to the first -floor residential flat and the installation of a rear dormer window. 1.2 A petition with 58 signatures in objection to the development was received in response to the initial consultation and another petition with 22 signatures in objection to the development was received following re-consultation on amended plans. The desired outcome of the petitions is for the application to be refused. Eleven separate representations have also been received in objection to the proposal (two from the initial consul tation and nine following subsequent re- consultations), as well as objections from the Northwood Residents Association and a local Ward Councillor. The main concerns raised within the representations include land ownership and boundary accuracy, the inclusion of car parking on public pavement (and the subsequent lack of parking associated with the scheme following the amendments received), pote ntial overdevelopment of the site, and the impact on the existing ground floor retail unit at 78 High Street. A full list of the matters raised in the consultation is included within Section 6 of this report. 1.3 Key planning considerations include the im pact of the proposal on the character and appearance of the surrounding area, including the Old Northwood Area of Special Local Character, the quality of accommodation for future occupiers, the impact on neighbouring residential amenity, highways and parking, and environmental considerations such as flood risk, sustainability and contamination. 1.4 Following the submission of amended plans, the application now proposes a car- free development with a corrected site boundary and design amendments that address earlier concerns raised by Planning Officers. 1.5 The Council’s Highways Officer raises no ob jection to the car-free nature of the development, noting its sustainable town centre location with good access to public transport and local facilities. The proposed housing mix is considered appropriate for the site and reflective of local housing need. All units meet or exceed internal space standards and pr ovide an acceptable level of light and outlook. Having regard to the site’s town centre context, historic plot pattern, and the high-quality design of the proposal, officers conclude that the scheme would not give rise to any significant harm to the character of the area or the amenity of adjoining occupiers. Hillingdon Planning Committee – 16th December 2025 PART 1 – Members, Public & Press 1.6 Taking all relevant matters into account an d giving due regard to local resident’s objections, including the petitions received against the proposal, it is considered that the proposal complies with the Development Plan when read as a whole and no material considerations indicate that a contrary decision should be taken. The planning application is therefore recommended for approval, subject to the conditions set out in Appendix 1. 2 The Site and Locality 2.1 The site is located on the eastern side of the High Street within Northwood Town Centre and comprises a two-storey semi-detached property. The site comprises a ground floor retail unit and first floor 2-be droom residential unit with a number of rear single-storey outbuildings used as a workshop, which are accessed along the side of the site. 2.2 The site lies in the Old Northwood Area of Special Local Character, the Northwood East Air Quality Focus Area and is within a Critical Drainage Area. The site has a Public Transport Accessibility Level (PTAL) of 2 and is within an area of potentially contaminative former land use. Figure 1: Location Plan (application site edged red) Hillingdon Planning Committee – 16th December 2025 PART 1 – Members, Public & Press Figure 2: Aerial view of application site in the context of surrounding development on the High Street Figure 3: Front view of the application site Hillingdon Planning Committee – 16th December 2025 PART 1 – Members, Public & Press Figure 4: View within the site looking north-west (76 High Street on the left) Figure 5: Front elevation of the site Figure 6: View within the site looking south-east (Beeches House in background) Hillingdon Planning Committee – 16th December 2025 PART 1 – Members, Public & Press Figure 7: South elevation of existing workshop buildings Figure 8: Rear elevation of 76 High Street Hillingdon Planning Committee – 16th December 2025 PART 1 – Members, Public & Press Figure 9: North elevation viewed from 80 High Street showing party wall Figure 10: Rear elevations of 76, 78 and 80 High Street 3 Proposal 3.1 The application seeks full planning permission to demolish the existing rear outbuildings and construct three new residential units with associated landscaping and bin / bike store. The party wall between the site and No. 80 High Street would be retained. The proposal includes alterations to the existing residential unit above the shop, including a rear dormer window . The following residential mix is proposed: Hillingdon Planning Committee – 16th December 2025 PART 1 – Members, Public & Press Unit 1 – modification to existing unit - two-storey 1-bed unit (above shop) Unit 2 – two-storey 2-bed unit with private terrace Unit 3 – single storey 1-bed unit Unit 4 – two-storey 3-bed unit with private garden 3.2 There have been a number of applications relating to the site over the past six years. Most recently, there were two previously refused planning applications and a withdrawn planning application. The main difference from the most recent scheme is that the previous proposal sought planning permission for the demolition of the existing workshop buildings, followed by construction of a pair of semi -detached 1.5 storey d wellings with associated pa rking and landscaping to the rear of the plot . However, the current proposal now seeks to re plicate the general built form of the workshops, as well as the construction of an attached two-storey dwelling with Dutch-roof fo rm at the rear end of the plot , with the dwellings set around a shared, enclosed courtyard. 3.3 The proposed development has been amended during the course of the application process to address concerns raised by officer’s relating to the proposed car parking to the front of the shop and some elements of the design of the dwellings to the rear. The amendments include the following: - Car parking spaces omitted - Red outline amended on location plan - Roof garden for unit 3 omitted - External staircase to roof garden omitted - Reduction in the size of the roof terrace for unit 2 - Insertion of rooflights to unit 3. Figure 11: Proposed Block Plan (please note – larger version of plan can be found in the Committee Plan Pack) Hillingdon Planning Committee – 16th December 2025 PART 1 – Members, Public & Press Figure 12: Proposed Ground Floor Plan (please note – larger version of plan can be found in the Committee Plan Pack) Figure 13: Proposed First Floor Plan (please note – larger version of plan can be found in the Committee Plan Pack) Figure 14: Proposed Second Floor Plan (please note – larger version of plan can be found in the Committee Plan Pack) Hillingdon Planning Committee – 16th December 2025 PART 1 – Members, Public & Press Figure 15: Proposed Roof Plan (please note – larger version of plan can be found in the Committee Plan Pack) Figure 16: Proposed Front Elevation (please note – larger version of plan can be found in the Committee Plan Pack) Figure 17: Proposed Rear Elevation (please note – larger version of plan can be found in the Committee Plan Pack) Hillingdon Planning Committee – 16th December 2025 PART 1 – Members, Public & Press Figure 18: Proposed Front Elevation Unit 4 (please note – larger version of plan can be found in the Committee Plan Pack) Figure 19: Proposed South Side Elevation (please note – larger version of plan can be found in the Committee Plan Pack) Figure 20: Proposed North Side Elevation (please note – larger version of plan can be found in the Committee Plan Pack) 4 Relevant Planning History 4.1 A list of the relevant planning history related to the property can be found in Appendix 2. 4.2 In February 2021 prior approval was sought for the conversion of existing retail unit to create 2 x 2 -bed apartments (Class C3) under Class M of the Town and Country Planning (General Permitted Development) (England) Order 2015 (as amended). This application was refused on 28 April 2021 (ref. 32265/APP/2021/710). Hillingdon Planning Committee – 16th December 2025 PART 1 – Members, Public & Press 4.3 An appeal was lodged against the refusal of the above prior approval application. The appeal was dismissed on 1 March 2022 . The Planning Inspector was of the view that insufficient information had b een presented to demonstrate that the workshops to the rear were in use for anci llary purposes to th e retail unit. The proposal therefore failed to accord with the requirements of paragraph M.1(a), and there was no certainty that it would constitute permitted development. 4.4 In April 2021 full planning permission was sought for the demolition of the workshop buildings and erection of a new 2 storey building containing 3 dwellings, parking and associated facilities including alterations to the existing building. The application was refused on 14 October 2021 for a number of reasons, including: harm to the character , appearance and visual amenities of the area; harm to residential amenity of surrounding properties; substandard accommodation proposed; lack of family-sized dwellings ; and lack of information relating to fire safety and refuse / recycling (ref. 32265/APP/2021/1437). 4.5 In June 2021 prior approval was sought fo r the conversion of the existing retail unit to create 2 x 1 -bed apartments (Class C3) under Class M of the Town and Country Planning (General Permitted Development) (England) Order 2015 (as amended). The application sought the change of use of the entire shop unit (i.e. including the retail shop at the front of the ground floor). This application was refused on 4 August 2021 on the grounds that: it would undermine the vitality and viability of the Northwood High Street Local Parad e; the proposed alterations to the front of the building would cause harm design and external appearance of the building; and that one of the units did not comply with the nationally described space standard (ref. 32265/APP/2021/2341). 4.6 In February 2022 full planning permission was sought for the demolition of existing buildings and erection of new 1.5 storey building containing 2 dwellings, parking and associated facilities. The application was refused on 1 June 2022 on the grounds that: the cramped, incongruous and visually obtrusive form of development would cause harm to the character, appearance and visual amenities of the surrounding area and th e wider Old Northwood Area of Special Local Character; it would cause harm to the living conditions of the neighbouring residential occupiers in terms of loss of outlook, perceived loss of privacy, overbearing impact and sense of enclosure; it would result in a substandard form of accommodation in terms of poor outlook, lack of defensible space and contrived layout; it provided a lack of family sized unit/s; insufficient amenity space; and lack of information on fire safety and accessibility (ref. 32265/APP/2022/579). 4.7 In April 2022 full planning permission was sought for the change of use of ground floor retail unit and ancillary storage area to one-bedroom apartment with external amenity space and associated facilities. The application was withdrawn on 8 June 2022 (ref. 32265/APP/2022/1231). 4.8 In August 2024 pre-application advice was sought for a scheme similar to that currently proposed. However, concerns were raised by Planning Officers regarding a communal rooftop garden and substandard quality of accommodation for future occupants. The current scheme has been amended to address the Hillingdon Planning Committee – 16th December 2025 PART 1 – Members, Public & Press issues raised within the pre-application advice letter. Amendments received during the course of the assessment are considered to have overcome Officers’ previous concerns, including where relevant, the reas ons for refusal relating to previous applications. 5 Planning Policy 5.1 A list of planning policies relevant to the consideration of the application can be found in Appendix 3. 6 Consultations and Representations 6.1 Twenty-two neighbouring properties and Northwood Residents Association were consulted on 21st February 2025. The consultation period expired on 14 th March 2025. Two individual letters of objection were received, as well as a petition (in objection) with 58 signatures, an objection from Northwood Residents Association and an objection from a local Ward Councillor. Internal and external consultations were also sent out and a summary of the comments received are noted below in Table 2 of this Committee Report. The main issue raised by residents during the initial consultation was the location of parking in front of the shop unit (a summary of all of the issues raised is shown in Table 1). 6.2 Re-consultation on revised drawings was carried out on 29 th October 2025 and the consultation period expired on 19th November 2025. Twenty-five neighbouring properties were consulted, as well as the Northwood Residents Association and the local Ward Councillor. The revisions included removal of parking (car free development now proposed), amended red outline on location plan, increase in size of cycle storage area for future residents, an internal refuse storage area was added for the shop unit, the roof terrace for unit 3 was removed , removal of external staircase for unit 3, increase in window size for unit 3 bedroom and a reduction in the terrace size for unit 2. 6.3 Following this second round of consultati on, eight individual letters of objection were received (six new objectors and two previous objectors), as well as a petition (in objection) with 22 signatures a nd a further objection from the Northwood Residents Association. The main issue raised by residents during the second round of consultation was the lack of parking (the full summary of all of the issues raised is shown in Table 1). 6.4 A third consultation was carried out on 4 th November 2025 following revisions to the application description (to accord with the current proposals). The consultation period expired on 25th November 2025. One individual letter of objection was received with concerns relating to aspects of the heritage report, harm to the continued operation of the shop and insufficient parking. A further revised drawing was received on 13 th November 2025, which included a WC on the ground floor plan for the shop unit. Another revised drawing was received on 4 th December 2025, which addressed minor discrepanc ies between the plans. It was not Hillingdon Planning Committee – 16th December 2025 PART 1 – Members, Public & Press considered necessary to re-consult on these two occasions, given the scale and nature of these minor amendments. 6.5 Representations received in response to public consultation are summarised in Table 1 (below). Consultee responses received are summarised in Table 2 (below). Full copies of the responses have also separately been made available to Members. Table 1: Summary of Representations Received Representations Summary of Issues Raised Planning Officer Response A valid residents petition with 58 signatures was received on 07- 03-2025 against the application, requesting refusal. 1. Car spaces directly in front of the shop unit will impede access to the shop. The car parking spaces have now been removed from the application. Parking is discussed at paragraphs 7.49-7.55 of this report. 2. The proposed flats and amenity space are cramped and will provide poor residential accommodation. Residential amenity and the quality of residential accommodation are discussed at paragraphs 7.27-7.47 of this report. A second valid residents petition received with 22 signatures was received on 12- 11-2025 against the application requesting refusal. 1. Removal of car parking spaces. On-site car parking spaces are a requirement, and there are on-street car parking restrictions. Parking is discussed at paragraphs 7.49-7.55 of this report. 2. Proposed development is overdevelopment of the site. The scale of development broadly replicates the outbuildings to the rear of the High Street. The scheme provides compliant internal space standards, acceptable levels of amenity, whilst optimising the capacity of an urban site. This is discussed at paragraphs 7.15-7.26 of this report. Hillingdon Planning Committee – 16th December 2025 PART 1 – Members, Public & Press 3. The amenity space on the roof has no disabled lift access. There is no requirement for every private external amenity space to be step- free. The unit is self- contained and does not rely on communal upper- level access. This is discussed at paragraphs 7.63-7.64 of this report. Eleven individual letters of objection received. I. Concerns over lack of parking, increased pressure on existing High Street parking, potential obstruction of pavements, impacts on deliveries, illegal parking near dropped kerbs, and general highway congestion. The Council’s Highways Officer raises no objection, noting the site’s sustainable town centre locatio n and proximity to public transport. No parking is proposed on the pavement or public highway. This is discussed at paragraphs 7.49-7.55 of this report. II. The proposal represents overdevelopment / backfilling of a small dense area, with insufficient space for parking, amenity, or circulation; references to nearby intensification such as the relocated library. The scale and massing is broadly following the footprint of the existing workshops. Level of accommodation vs. amenity / services are considered acceptable for an urban town centre location. This is discussed at paragraphs 7.15-7.26 of this report. III. Overlooking from upper- level amenity space, loss of outlook and loss of the existing side access / drive space. Residential amenity is discussed at paragraphs 7.27-7.37 of this report. IV. Use of shop will be negatively affected by loss of storage space, proposed development would harm the long- standing shop, affect its visibility and operations, and potentially result in the tenant losing both her home and livelihood. The ground-floor retail unit would be retained with a smaller storage area and would be able to continue to function independently of the proposed residential development. The revised scheme removes parking, ensuring pedestrian access. The applicant has advised that the shop unit would continue to operate as a self-contained retail Hillingdon Planning Committee – 16th December 2025 PART 1 – Members, Public & Press unit. Officers are satisfied that the proposed development would not prejudice the continued operation of a retail unit. Thiis discussed at paragraphs 7.4-7.9 of this report. V. Comments alleging misinformation in the application, lack of information within the Heritage Report, concerns over land ownership, adequacy of consultation (including not receiving amended plans), and the perception that the scheme is profit- driven at the expense of established businesses. The impact on heritage (i.e. on the Area of Special Local Character at discussed in paragraphs 7.15 -7.26 of this report. The red line boundary has been corrected. Consultation was carried out in accordance with statutory requirements, including re -consultation on amended plans. Profit motive is not a material planning consideration. VI. Concerns about parking arrangements, noting that the shop tenant currently parks in the alley beside the shop. The proposed development would result in the loss of the alleyway adjacent to the property that is informally used for parking by the shop tenant. This area is not a formally designated parking bay, nor does it benefit from any planning status as private parking. As such, the loss of an informal parking arrangement cannot be afforded significant weight and would not constitute reasonable grounds to refuse the application. The Council’s Highways Officer has also confirmed that a car -free scheme is acceptable in this town centre location, subject to the recommended conditions. Parking is discussed in paragraphs 7.49-7.55 of this report. Hillingdon Planning Committee – 16th December 2025 PART 1 – Members, Public & Press Northwood Residents Association (Comments on initial consultation) i) Incorrect red line boundary ii) Parking proposed on pavement in front of shop would obstruct the shopfront, harm pedestrian movement, adversely affect the tenants trade and would set a precedent for pavement parking elsewhere in the Borough. iii) The lack of on-site parking shows that the site is too cramped for the scale of development proposed. Plans show no feasible access for vehicles to the rear of the site. iv) Scheme is cramped, with poor internal layouts, inadequate amenity space, and concerns regarding accessibility of roof terraces. v) Scale and intensity of development constitute overdevelopment, with lack of on-site parking, accessible amenity space, or safe children’s play space. The red outline on the location plan has been amended. Parking has been removed from the proposal. The scheme follows the site’s historic rear-plot pattern and the footprint would be considered similar to the existing built footprint . The density is appropriate for a small brownfield site in a town centre location . This is discussed at paragraphs 7.38-7.47 of this report. This is discussed at paragraphs 7.15-7.26 of this report. Northwood Residents Association (Comments on amended plans) i.) Overdevelopment, site is too cramped for the scale of development proposed. ii.) No onsite parking and no vehicular access to the rear and that This is discussed in paragraphs 7.15-7.26 of this report. Parking is discussed in paragraphs 7.49-7.55 of this report. Hillingdon Planning Committee – 16th December 2025 PART 1 – Members, Public & Press approval would set precedent. iii) Concerns about accessibility of rooftop amenity space. The Access Officer has reviewed the application and raised no objections. There is no requirement for every private external amenity space to be step- free. Accessibility is discussed in 7.63-7.64 of this report. Local Ward Councillor Concerns regarding: 1. Continued viability of the shop unit 2. Parking and pedestrian safety Viability of the retail unit is discussed in paragraphs 7. 4-7.9 of this report. In terms of pedestrian safety, the parking has been removed from in front of the shop. Highway safety and parking are discussed in paragraphs 7.48-7.59 of this report. Table 2: Summary of Consultee Responses Consultee and Summary of Comments Planning Officer Response Highways Officer: No objection. Following amendments to remove the car parking spaces from the scheme, the application has been reviewed by the Highway Authority who are satisfied that the proposal would not discernibly exacerbate congestion or parking stress, and would not raise any measurable highway safety concerns, in accordance with Policies DMT 1, DMT 2 and DMT 6 of the Local Plan Part 2 and Policies T4, T5 and T6 of the London Plan. The Highways Officer recommends that a full construction management plan be secured by condition given the constraints and sensitivities of the immediate road network in order to avoid/minimise potential detriment to the public realm. The comments from the Highways Officer are noted and the relevant condition is recommended to be added to the decision notice. This is discussed at paragraph 7.48-7.59 of this report. Urban Design Officer: No objection. The amendments have overcome previous concerns raised. The Urban Design Officer These comments are noted, and the quality Hillingdon Planning Committee – 16th December 2025 PART 1 – Members, Public & Press has recommended that details of the external materials be secured by condition. of design is discussed at paragraph 7.15-7.26 of this report. Access Officer: No objection subject to the inclusion of a ‘step free access’ condition and a condition requiring the submission of certification of compliance with M4(2) accessibility regulations prior to occupation. The comments from the access officer are noted and the relevant conditions are recommended to be added to the decision notice. This is discussed at paragraphs 7.63-7.64 of this report. Waste Officer: No objection. Noted. Contaminated Land Officer: No objection subject to condition. A contaminated land condition is recommended to include submission of a desktop study, site investigation and written method statement prior to commencement of development. This is discussed at paragraph 7.77 of this report. 7 Planning Assessment Principle of Development 7.1 The application site is located within an established urban area in Northwood Town Centre, wherein the principle of residential development is acceptable in accordance with Policy BE1 of th e Hillingdon Local Plan Part 1. The application site relates to previously developed land, wherein substantial weight is given to the value of using suitable brownf ield land within settlements for homes . The proposed development would extend deep into the plot (albeit on a similar footprint to the existing buildings within the site). Related to this, policy DMH 6 of the Local Plan Part 2 relates to ‘garden and backl and development’. The associated policy text at para 4.15 of the L ocal Plan Part 2 clarifies that ‘In general, the Council will not accept proposals for developments on garden land but proposals for development of backland sites in other uses will be considered subject to the Hillingdon Planning Committee – 16th December 2025 PART 1 – Members, Public & Press criteria in Policy DMH 6: Garden and Backland Development and other relevant policies.’ 7.2 In this case, the site is not considered to constitute garden land and the principle of development can therefore be supported, subject to consideration of the criteria contained within Policy DMH 6 and other relevant policies discussed within this report. The criteria set out within Policy DMH 6 are listed below for ease of reference and it is considered that these criteria are satisfied, as discussed within the corresponding sections of this report: 7.3 i) neighbouring residential amenity and privacy of existing homes and gardens must be maintained and unacceptable light spillage avoided; ii) vehicular access or car parking should not have an adverse impact on neighbours in terms of noise or light. Access roads between dwellings and unnecessarily long access roads will not normally be acceptable; iii) development on backland sites must be more intimate in mass and scale and lower than frontage properties; and iv) features such as trees, shrubs and wildlife habitat must be retained or re- provided. 7.4 The site comprises a retail unit (Use Class E) and, as the proposed development would result in the loss of ancillary structures to the rear of the site, any loss of commercial floor space must also be considered. Loss of Commercial Floor Space 7.5 Policy SD6 of the London Plan seeks to promote and enhance the vitality and viability of London's varied town centres and Policy DMTC 3 of the Hillingdon Local Plan Part 2 requires the Council to protect and enhance the function of local centres and local shopping parades by retaining uses that support their continued viability and attractiveness to the locality they serve. Policy DME 2 of the Hillingdon Local Plan Part 2 states that proposals which involve the loss of employment floorspace will normally be permitted if, inter alia: the site is unsuitable for employme nt reuse because of its size, shape, location, or unsuitability of access; sufficient evidence has been provided to demonstrate there is no realistic prospect of land being reused for employment purposes; or the new use will not adversely affect the functioning of any adjoining employment land. 7.6 The proposal comprises the redevelopment of floor space shown on the plans to the rear of the retail unit as stor e, kitchen and workshop. The applicant has confirmed that these elements do not form part of the existing retail unit. Moreover, it is understood that the workshop had not been used for ancillary purposes to the retail unit in recent years and was leased separately. 7.7 In terms of the workshop and store areas to the rear of the retail unit, whilst no marketing evidence has been provided to demonstrate that the existing use is no longer viable, it is acknowledged that these elements have no active frontage and therefore make a limited contribution to the High Street shopping parade. Any Hillingdon Planning Committee – 16th December 2025 PART 1 – Members, Public & Press business operating from this space woul d require customers to access the premises via a private driveway, reducing its attractiveness and commercial potential. It is also recognised that the overall quality of the existing workshop and store areas are in a dilapidated state and would require significant works to bring the buildings to acceptable quality for commercial use. These factors lessen the weight of harm associated with the loss of floorspace. 7.8 Regard is also given to a recent appeal decision for 82-84 High Street, Ruislip (LPA ref. 78935/APP/2024/1992, PINs ref. APP/R5510/W/24/3356952) , which included the partial change of use of the ground floor commercial space to provide ancillary facilities for residential flats. Of relevance to the consideration of this application is that the Inspector concluded that, whilst works to the rear of the site to provide ancillary facilities to serve proposed residences would result in the loss of retail floorspace, overall it would not cause harm to the marketability of the ground floor retail unit or to the wider function and vitality of the town centre. It is considered that the current proposal is similar, in that the primary retail unit would remain unaffected, retaining an active frontage and continuing to contribute to the vitality of Northwood town centre. The rear element proposed for demolition has no direct customer access and provides limited commercial value, meaning its loss is unlikely to compromise the attrac tiveness or viability of the ground floor retail use, which would retain an active frontage, or the wider shopping parade. 7.9 As a result of the proposed development, the main retail floor space for the shop unit would be retained and a small store with WC created to serve it. On balance, the proposal is not considered to signif icantly undermine the vitality and viability of Northwood High Street Local Parade or the Borough’s employment land provision. The proposal would still provide a viable commercial retail unit to operate at the site. Housing Need 7.10 Paragraph 124 of the NPPF promotes the efficient use of land to meet housing needs and London Plan Policy GG4 seeks to ensure that more homes are delivered, whilst Policy H1 of the Hillingdon Local Plan Part 1 provides that the Council will seek to meet and exceed it s housing growth targets, with Policy T1 steering development to the most appropri ate locations in order to reduce their impact on the transport network and encourage access by sustainable modes including cycling and walking. There is no objection in principle to introducing residential development to the rear of the site. It is noted that the Council currently has a five-year supply of deliverable housing sites, t herefore, the “tilted balance” under paragraph 11(d) of the NPPF does not apply. Nevertheless, the modest, net contribution of 3 residential units weighs in favour of the proposal. Principle Conclusion 7.11 Taking all of the above into account, it is considered that the proposed redevelopment of the site is acceptable, subject to the below assessment. Hillingdon Planning Committee – 16th December 2025 PART 1 – Members, Public & Press Housing Mix 7.12 Policy H10 of the London Plan states that schemes should generally consist of a range of unit sizes and sets out a number of factors which should be considered when determining the appropriate housing mix on a particular scheme, including local evidence of need. Policy DMH 2 of the Hillingdon Local Plan Part 2 requires the provision of a mix of housing units of different sizes in schemes of residential development to reflect the Council's latest information on housing need. Paragraph 4.6 outlines that there is a substantial borough-wide requirement for larger affordable and private market units, particularly three-bedroom properties. 7.13 In terms of factors specific to a site, Policy H10 also includes a need to consider the mix of uses in the scheme, the range of tenures in the scheme and the nature and location of the site, with a higher proportion of one and two bed units generally more appropriate in locations which are closer to a town centre or station or with higher public transport access and connectivity. 7.14 The proposed development would result in an acceptable mix of tenures. The site has a PTAL of 2 and is located within Northwood Town Centre. Given the location and connectivity of the site, officers accept that a higher proportion of one and two bed units are generally more appropriate in this location. Considering the site- specific characteristics and design constraints of the rear site location, it is also considered the provision of only one family sized unit is appropriate . The family sized unit makes a welcome (albeit modest) contribution to the recognised need for family housing within the Borough, and a planning condition has been recommended to prevent conversion of this unit to a small HMO C4 unit ( without express planning permission), in order to retain a suitable housing mix. Design / Impact on the Character and Appearance of the Area 7.15 Paragraph 135 of the NPPF, Policy D4 of the London Plan and Policy BE1 of the Hillingdon Local Plan Part 1 require development proposals to be of high -quality design and seek to ensure that new development delivers buildings and spaces that are sympathetic to local character and distinctiveness, including the surrounding built environment. Policy D3 of the London Plan seeks to optimise site capacity through a deign-led approach , rather than limiting development by quantitative thresholds. 7.16 Policy DMHB 11 of the Hillingdon Local Plan Part 2 seeks to ensure that new development harmonises with the surrounding area, and that new development respects adjoining properties in terms of layout, scale, height, bulk and materials. The site also lies within the Old Nor thwood Area of Special Local Character (ASLC), wherein Policy DMHB 5 requires development to preserve or enhance those features which contribute to the s pecial character and appearance of the area, including its traditional plot layout, building forms, and materials. 7.17 The surrounding area comprises a mix of commercial, retail and residential uses. The Old Northwood ASLC is char acterised by traditional late -Victorian and Edwardian buildings of varied architectural style but uniformity in scale, materials, Hillingdon Planning Committee – 16th December 2025 PART 1 – Members, Public & Press and roof forms. Whilst the proposed development would be positioned to the rear of 78 High Street, it would nonetheless be partly visible in glimpsed views from the public realm along High Street. The site is considered to form part of the historic rear plot pattern that contributes to the area’s significance. 7.18 The current scheme follows a previously refused scheme (LPA ref. 32265/APP/2022/579) for the redevelopment of the site to provide a pair of semi- detached 1.5-storey one-bedroom dwellings with vehicular access off the High Street and associated parking and amenity space within the plot. The application was refused on the grounds that it would appear cramped and visually intrusive, causing significant harm to the character and appearance of the Old Northwood ASLC. It was also refused on the grounds that it would adversely affect neighbouring occupiers through loss of outlook, loss of privacy, and an overbearing sense of enclosure. Furthermore, the scheme proposed substandard living conditions for future residents due to poor outlook, lack of defensible space, and inadequate private amenity provision. 7.19 The previous scheme extended across the full width of the site, measuring 8.1m wide and 11.8m deep with a ridge height of 7.8 m. It comprised parking for two vehicles, a parking turntable and a shared amenity space measuring 40sqm. It sought to retain the store, kitchen and WC attached to the rear of 78 High Street, with the workshop proposed for demolition. It was considered that the overall scale and configuration of the previous scheme would have resulted in a cramped and contrived form of development. 7.20 In comparison, the current proposal w ould retain the party wall and demolish the existing low-rise workshop buildings to the rear of the site, replacing them with three self-contained dwellings arranged around a shared courtyard. This would consist of a two-storey (part single storey) extension to the existing rear outrigger and a new build dwelling to the rear, however overall, the massing and footprint would broadly replicate that of the existing outbuildings (see Figures 21 and 22 below for a comparison of built form). The new build dwelling would span the width of the site, however it would have a lower ridge height than the previous refused scheme (measuring 6m in height) and would not be as deep (measuring 7.2m in depth). The scale and height of the dwelling to the rear would appear more modest and intimate within its location than the previous submission. The Dutch gable style roof further reduces the bulk to the rear from the previous schemes before, which were more akin to two storey full height dwellings. 7.21 Generally, the proposed buildings range from single to two storeys in height, with the rearmost dwelling featuring a Dutch-gabled roof form and unit 2 comprising a flat green roof. Unit 1 (above the shop) would have a rear -facing dormer window. External finishes are proposed to comprise facing brickwork with timber cladding feature panels below the window openings and a zinc standing seam roof to the rearmost unit (unit 4). The dormer cheeks would be finished in hanging roof tiles to match the main roof. Unit 2 would comp rise a private external terrace and unit 4 would have a private rear garden. The proposed density would be 111 dwellings per hectare, which sits within the medium density range for an urban, PTAL 2 Hillingdon Planning Committee – 16th December 2025 PART 1 – Members, Public & Press location, consistent with the previous London Plan guidance and acceptable under the design-led density approach in the current London Plan. Figure 21: Existing SW Side Elevation – see comparison with proposed side elevation in Figure 22 below. Figure 22: Proposed SW Side Elevation – for comparison of existing vs. proposed massing. The orange outline denotes the extent of the existing buildings. 7.22 The proposed built form would replicate t he general siting of existing structures, however with a larger footprint than the existing built form on the site. Nonetheless, it is considered that the proposed develop ment would not disrupt the prevailing pattern of development or the historic plot structure to the rear of High Street properties, which typically feature outbuildings and ancillary structures. Concerns have been raised during the consultation process that the proposal represents overdevelopment. However, in the context of Policy D3 of the London Plan, which requires a design-led approach to optimising site capacity, it is considered that the scheme would deliver an appropriately scaled development for the town centre location. Furthermore, the limited visibi lity of the scheme from the High Street, combined with its low profile and symp athetic design, would ensure that the proposal would preserve the special c haracter and appearance of the Old Northwood ASLC. 7.23 The proposed scheme also introduces an enhanced landscaping strategy, which was absent from the previously refused application. The incorporation of defensible planting within the courtyard, green roof to unit 2 and additional soft landscaping to the rear garden of unit 4 would contribute positively to the visual quality of the development and provide a degree of greening within an otherwise hard-surfaced town centre environment. The courtyard arrangement would create Hillingdon Planning Committee – 16th December 2025 PART 1 – Members, Public & Press a semi-private, enclosed space that is appropriate for the site’s High Street setting and helps to soften the built form when viewed from neighbouring properties. 7.24 It is also noted that several comparable structures exist to the rear of commercial units within the immediate vicinity, inclu ding the development immediately to the rear of the site at 80 High Street (Beeches House), 1 Fords Place (accessed off Hilliard Road) and 56b High Street (to the rear of 56 High Street). These developments reflect a historic pattern of secondary buildings and mews- type development behind the High Street frontage. The proposed built form would therefore sit comfortably within this established context and would not appear incongruous or out of character. 7.25 The Council’s Urban Design Officer has been consulted and, following amendments to the scheme, has raised no objection to the proposal subject to the inclusion of planning conditions securing details of materials. 7.26 Taking all of the above into account, the proposed development is considered to represent a n appropriate design response that assimilates into its context and preserves the character and appearance of the surrounding area and the ASLC. Furthermore, given the site’s u rban town centre location, it is considered that the proposed density is consistent with the surrounding pattern of built form and in line with the design-led approach to optimising site capacity as set out in Policy D3 of the London Plan. Subject to the inclusion of the above- mentioned condition, the proposal complies with the above policies in terms of its impact on the character and appearance of the area. Residential Amenity 7.27 Paragraph 135 f) of the NPPF and Policy D3 of the London Plan outline the importance of planning in securing good standards of amenity for existing and future occupiers of land and buildings. Policy DMHB 11 of th e Hillingdon Local Plan Part 2 seek s to ensure that new development does not result in a detrimental impact upon adjacent properties and their amenity space in terms of outlook, privacy, amenity and daylight / sunlight. 7.28 The impact on future occupiers is discussed below in the ‘Quality of Residential Accommodation’ section below. In terms of existing occupiers, the nearest residential properties are flats located at 76 and 80 High Street, i.e. on either side of the application site, and Beeches House to the rear. 7.29 At first floor level there would be two side-facing windows serving the bathrooms for units 1 and 2. However, these would be secured as obscure glazed and non- opening below 1. 7m of internal floor level, to mitigate any potential loss of privacy. The proposed rear-facing dormer would have oblique views over 76 and 80 High Street, however it is not felt that this would give rise to any significant overlooking. The proposed terrace for unit 2 could give rise to views over 76 High Street, however a screen is proposed on the side of the terrace, therefore mitigating any significant potential overlooking or loss of privacy. Hillingdon Planning Committee – 16th December 2025 PART 1 – Members, Public & Press 7.30 In relation to Beeches House to the rear of the site, there would be rear-facing windows at first floor level serving the bedrooms and hallway of unit 4. There are existing rooflights within the west -facing roof slope of Beeches House, however they would not be directly opposite the proposed windows for unit 4, rather they would be at an offset angle. This relationship is considered acceptable. 7.31 In terms of visual impact, the majority of the proposed built form would replace the bulk and mass of the existing workshop buildings. There would be an increase in built form as a result of the two -storey extension to the rear outrigger, however from the perspective of 80 High Street, only circa 0.7m of new built form would be visible above the existing party wall. In relation to 76 High Street, the increase in built form would be more apparent, however as outlined below, whilst the two- storey rear extension would be visible, it would nonetheless have an acceptable impact in terms of light provision. 7.32 Similarly, unit 4 would be visible from surrounding residential properties, however by virtue of its low-profile roof, it is not considered that the built form of unit 4 would be visually overbearing to existing occupiers. 7.33 In relation to the impact on light provision, a daylight and sunlight assessment has been submitted in support of the proposal . The analysis considered the potential effects of the proposed development on the daylight and sunlight received by neighbouring properties, including 76 and 80-82 High Street and Beeches House to the rear. The assessment used the Vertical Sky Component (VSC) to evaluate daylight and Annual Probable Sunlight Hours (APSH) to assess sunlight availability. 7.34 The results demonstrate that all 18 windows assessed pass the criteria set out in the 2022 BRE guidelines for daylight and sunlight - Site layout planning for daylight and sunlight: a guide to good practice. All windows would retain in excess of 80% of their existing VSC values, meaning that no material loss of daylight would occur to any neighbouring window. Similarly, all windows facing within 90 degrees of due south would continue to receive sunlight levels exceeding the BRE targets for both annual and winter periods. The assessment also confirmed that the neighbouring garden areas would continue to receive at least two hours of sunlight over more than 50% of their area on 21 March, fully meeting the BRE criteria for overshadowing. 7.35 In terms of outlook and sense of enclo sure, the proposed development would replace the existing single- storey workshop structures, resulting in modest additional massing when viewed from adjoining properties. Although the two- storey extension to the rear outrigger increases the height of built form in proximity to 76 and 80 High Street, it is not cons idered that it would be unduly visually intrusive due to its separation from the shared boundar y with No. 76 and the presence of the party wall on the boundary with No. 80. Similarly, unit 4, positioned to the rear of the plot, incorporates a low -profile roof form that reduces overall massing and would mitigate any unduly oppressive sense of enclosure when viewed from Beeches House. Hillingdon Planning Committee – 16th December 2025 PART 1 – Members, Public & Press 7.36 It is considered that the proposal would not result in any unacceptable loss of daylight / sunlight, loss of privacy and would not create an unacceptable sense of enclosure for surrounding occupiers. 7.37 Taking all of the above into account, it is considered that the proposed development would provide a good standard of amenity for existing occupiers, to accord with paragraph 135 f) of the NPPF, Policy D3 of the London Plan, and Policy DMHB 11 of the Hillingdon Local Plan Part 2. Quality of Residential Accommodation (Internal and External) Internal Accommodation 7.38 Regarding internal accommodation, Policy D6 of the London Plan sets out the requirements for the gross internal floor area of new dwellings at a defined level of occupancy. Table 3.1 of the London Plan set outs the same gross internal area space standards set out in the Technical Housing Standards - Nationally Described Space Standard. Policy DMHB 16 of the Local Plan Part 2 aligns with this policy. 7.39 All four units meet or exceed the minimum overall gross internal area requirements for their respective occupancy levels. Bedrooms generally comply with the London Plan minimum sizes for single and double rooms and the overall size and layout of the proposed units would provide living spaces that are functional and commensurate with urban locations. 7.40 Outlook from the ground floor habitable rooms for units 2 and 3 would project onto a semi-private courtyard area which include s a substantial buffer of high- quality defensible landscaped space, which would be secured by condition. Defensible landscaping would also provide mutual privacy mitigation between the bedroom window of unit 3 and the kitchen window of unit 4, which are perpendicular to each other. Although the proposed one-bedroom unit (unit 3) would be single- aspect, the overall quality of accommodation is considered acceptable, with an efficient layout, compliant room sizes and a reasonable outlook supported by the landscaped area to the front. As such, the single -aspect nature of the unit is not considered to warrant refusal in this instance. All other residential units proposed would provide a dual aspect arrangement. 7.41 In terms of light provision, it is considered that all proposed units would receive an adequate level of natural daylight. Unit 3 has been amended to include obscure glazed rooflights to ensure that all rooms within this flat receive adequate daylight. 7.42 In terms of privacy, separation distances between the proposed units and existing neighbouring properties are considered appropriate for an urban location. The inward-facing courtyard layout limits opportunities for direct overlooking. External Amenity Space 7.43 With regard to external amenity space, Policy DMHB 18 of Local Plan Part 2 states that all new residential development and conversions will be required to provide Hillingdon Planning Committee – 16th December 2025 PART 1 – Members, Public & Press good quality and usable private outdoor amenity space. Amenity space should be provided in accordance with the standards set out in Table 5.3, which requires the following: 1-bedroom flat: 20 sqm 2-bedroom flat: 25 sqm 3-bedroom house: 60 sqm 7.44 Unit 2 would have a private first-floor te rrace measuring approximately 12.7sqm and unit 4 proposes a private garden area to the rear, measuring approximately 57 sqm . It is considered that the terrace for unit 2 would provide a small but functional outdoor space, and unit 4’s garden is of a size and quality that would serve the needs of a family unit (albeit marginally below the size requirement quoted above). 7.45 The retained first-floor flat above the shop (unit 1) and unit 3 do not include private external amenity space, however this si tuation is not uncharacteristic of town centre locations, particularly for small starter homes that have good access to public open space, or example Northwood Recreation Ground, which is within 7 minutes’ walk. 7.46 It is also worth noting that the existing residential unit above the shop comprises two bedrooms and does not currently have access to a private outdoor amenity space. Unit 1 would be reduced to a one -bedroom unit, such that the overall quantum of bedrooms without access to private outdoor space would remain comparable to the existing situation. Overall, it is considered that the level of external amenity provision is acceptable for the urban location. 7.47 On balance, it is considered that the proposed development would provide a good standard of amenity and accommodation for future occupiers, to accord with paragraph 135 f) of the NPPF, Polic ies D3 and D6 of the London Plan and the objectives of Policies DMHB 11, DMHB 16 and DMHB 18 of the Hillingdon Local Plan Part 2. Highways and Parking 7.48 The Highways Officer has reviewed the scheme and has raised no objection to the application, noting that the proposal would not discernibly exacerbate congestion or parking stress, and would not raise any measurable highway safety concerns. Parking 7.49 Policy DMT 6 of the Hillingdon Local Plan Part 2 states that new development will only be permitted where it accords with the council's adopted parking standards unless it can be demonstrated that a deviation from the standard would not result in a deleter ious impact on the surrounding road network. Policy T6 of the London Plan supports car-free development in areas that are well- connected by public transport, particularly within town centres. Policy T6.1 of the London Plan requires Hillingdon Planning Committee – 16th December 2025 PART 1 – Members, Public & Press that new residential development should not exceed the maximum parking standards as set out in table 10.3. 7.50 The maximum requirement for the proposed development under the London Plan would be up to three on-plot spaces. The scheme is proposed as car- free, which is considered acceptable given the site-specific circumstances as detailed below. 7.51 The site is located in a town centre location with good access to local public transport routes, with the nearest bus stop within 40m of the site and the nearest underground station located within 13 minutes’ walk. In addition, the development includes secure cycle storage for residents, and it is considered that Northwood comprises a range of facilities and services within walking distance. 7.52 Parking restrictions are in place on Northwood High Street where waiting restrictions operate between 8:00am and 6:30pm Monday to Saturday on the eastern side. Whilst the western side la cks formal restrictions, the presence of numerous vehicle crossovers significan tly limits the availability of on- street parking. 7.53 The Highway Officer has confirmed that fu ture residents would not be eligible to apply for a parking permit . To qualify for a permit the address must be located within a controlled parking zone, which the site is not thus futu re residents are precluded from applying for a permit. 7.54 Small sites with constrained access are ex plicitly recognised as appropriate for car-free proposals, provided the scheme does not lead to overspill parking pressures. Given the above site- specific circumstances, it is considered that overspill parking will not be likely. 7.55 Taking all of the above into account, it is considered that the lack of on-street parking (and lack of parking permit) would be a significant constraint on car ownership and would encourage the use of sustainable travel modes. The proposal complies with the sustainable transport objectives of the London Plan and the NPPF and the absence of on-plot parking would not result in a severe impact on the highway network. In accordance with p aragraph 116 of the NPPF, refusal on transport grounds should only occur where the residual cumulative impacts would be severe. Cycle Parking 7.56 In terms of cycle parking there should be one secure and accessible space for the flatted units and two spaces for the larger unit. A secure bike store is proposed at ground floor level, which is considered an acceptable arrangement. Operational Refuse Requirements 7.57 Refuse collection would take place via the High Street. In order to conform to the council's 'waste collection' maximum di stance collection parameter of 10m i.e. distance from a refuse vehicle to the point of collection, arrangements should Hillingdon Planning Committee – 16th December 2025 PART 1 – Members, Public & Press ensure that waste is positioned at a collec tion point within this set distance. A revised bin store location is proposed toward the frontage of the address which conforms to waste collection distance standards. Construction Management Plan (CMP) 7.58 A full CMP is required, given the constr aints and sensitivities of the immediate road network in order to avoid/minimise potential detriment to the public realm. It is recommended that the CMP be secured by condition. Conclusion 7.59 The application has been reviewed by th e Highway Authority who are satisfied that the proposal would not discernibly ex acerbate congestion or parking stress, and would not raise any measurable highway safety concerns, in accordance with Policies DMT 1, DMT 2 and DMT 6 of the Local Plan Part 2 and Policies T4, T5 and T6 of the London Plan. Noise 7.60 Policy D14 of the London Plan requires that proposals minimise noise pollution and Policy EM8 of the Hillingdon Local Plan Part 1 promotes the maximum possible reduction in noise levels and seeks to ensure that noise impacts can be adequately controlled and mitigated. 7.61 The site would be used in an exclusively residential capacity. Therefore, in terms of the operational phase of the pro posed development (occupation of the dwellings), no significant issues are raised by the proposal in respect to noise. 7.62 Given the built-up residential nature of the area, a Construction Management Plan would be necessary to minimise noise and other emissions caused during the construction phase as far as practicable. This would be secured by condition. Accessibility 7.63 Policy D5 of the London Plan seeks to ensure development proposals achieve the highest standards of accessible and inclu sive design. Policy D7 of the London Plan requires at least ten percent of dwellings to meet Building Regulation requirement M4(3) 'wheelchair user dwellings', with all other dwellings meeting Category M4(2) 'accessible and adaptable dwellings'. 7.64 The Council’s Access Officer has been consulted on the application and has raised no objection to the proposed development in terms of accessibility, subject to the inclusion of conditions pertaining to ensuring step free access and requiring

Meeting: Hillingdon Planning Committee Date: 16 December 2025 Time: 7:00pm Venue: Council Chamber, Civic Centre ADDENDUM SHEET Item: 6 Location: Heathrow Airport Amendments/Additional Information: Officer Comments: The final element of the ultrafine particle (UFP) Heads of Term has now been agreed as set out below: Prior to commencement of the development, UFP monitoring and action plans for ultrafine particles (UFP) shall be submitted in writing to the Council for approval. The Monitoring Plan shall include the location of and operating parameters of one additional monitor (funded by the applicant) and will set out an appropriate methodology for collecting and reporting data. The plan will be kept under review and amendments made with agreement from both parties. The UFP Action Plan shall set out how monitoring data will be reviewed and evaluated and how the applicant is responding to and observing any current national policy or statutory targets for UFPs, where these exist and so far as they relate to the development. The UFP Action Plan will be reviewed and submitted to the Council for approval every 4 years to consider monitoring outputs, and to provide assurance that any relevant national policy developments are being observed. For completeness Comments received from Surrey County Council (summary): SCC supports the collective HSPG response but wishes to highlight key concerns. Heathrow’s operations must continue to rely on established noise-reduction measures, including night-time restrictions and full runway alternation that guarantees predictable respite. SCC stresses that the current planning application must not enable “full” mixed- mode operations by stealth, as any reduction in alternation would undermine the purpose of ending the Cranford Agreement, which was to secure full alternation for communities west of the airport. Mixed-mode operations— full or partial— have not been assessed in the environmental Operational conditions are discussed at paragraphs 8.5 to 8.14 of this report. impact assessment, so SCC seeks a planning condition legally requiring continued full alternation and restricting mixed-mode use to exceptional emergencies only. SCC has no concerns about the physical enabling works or construction impacts, but it does have concerns about operational impacts on Surrey. Ending the Cranford Agreement will increase arriving flights over Stanwell and Stanwell Moor, raising noise levels in areas currently protected from easterly landings. While parts of these communities already qualify for relocation or insulation schemes, no additional mitigation is proposed for wider Stanwell. SCC therefore requests detailed monitoring of actual noise impacts during the first five years of modified operations, with a process to identify and support any newly affected properties. The Residential Insulation Scheme must remain open to future applicants and should not impose time limits that exclude households affected later. Mitigation should also cover all community buildings—not just schools—including early years settings, places of worship, and community facilities, ensuring comparable protection standards. Noise pollution is discussed at paragraphs 7.26 to 7.185 of this report. People and Communities are discussed at paragraphs 7.227 to 7.234 of this report. Amend Paragraph 7.286 as follows: ‘The ES chapter concludes that the proposed development will have no significant adverse effects on the historic environment and the noise barrier does not harm the character or setting of Longford Conservation Area or listed buildings. In terms of noise pollution, it is recognised that there may be some limited harm to heritage assets, including Richmond Park, which is a Grade I listed registered Park and Garden. However, it is considered to be less than substantial harm which, when weighed against the public benefits of bringing greater equity of noise pollution and providing predictable respite, is deemed acceptable. The council’s Conservation Officer has reviewed the submitted details and they have confirmed they agree that heritage assets would not be significantly harmed by the proposals. Officers therefore agree with the conclusions that are drawn in the ES and it is considered that the proposals accord with relevant planning policies quoted above.’ For clarity Amend paragraph 7.170 as follows: ‘It is noted that it is already overflown significantly when the airport operates on westerlies, though it is accepted that it would receive some adverse impacts from the development. However, Richmond Park is further from the main source of noise and therefore only marginal changes in the noise impacts have been identified. Consequently, it is considered that the less than substantial degree of harm in certain areas of the park is outweighed by some benefits to the park elsewhere, as well as the wider public benefit of providing a more equitable distribution of noise.’ For clarity Additional Condition: ‘The development hereby permitted shall not be brought into operation unless in accordance with the specified supporting plans and/or documents: - Easterly Alternation Infrastructure Project EIA Environmental Statement (October 2024) - Design and Access Statement (October 2024) - Flood Risk Assessment (November 2024) Thereafter the development shall be retained/maintained in accordance with these details for as long as the development remains in existence REASON To ensure the development complies with the provisions of Hillingdon Local Plan Parts 1 (November 2012) and 2 (January 2020) and the London Plan (2021).’ For completeness Amended Condition 10 ‘Sustainable Water Management’: Prior to commencement (except for demolition, ground and enabling work) of any relevant phase of this development, a scheme for the provision of sustainable water management shall be submitted to, and approved in writing by the Local Planning Authority in consultation with the relevant stakeholders. The scheme shall clearly demonstrate how it manages water and demonstrate ways of controlling the surface water on site by providing information on: a) Sustainable Drainage features: i. Surface water discharge - the submitted drainage strategy must identify the proposed method and location of discharging collected surface water from the site in reference to the hierarchy set out in Policy SI 13 of the London Plan (2021). Where the proposal does not utilise the most sustainable solution, justification must be provided. ii. SuDS - the submitted drainage strategy should incorporate Sustainable Drainage System (SuDS) elements, where practicable. iii. Exceedance routes - provide a plan showing the route surface water will take through the development for rainfall events exceeding the 1 in 100 year event. Where it is intended to store water on the ground surface, the maximum extent of overland flooding should be mapped and the depth of the flooding confirmed. b) Long-term management and maintenance of the drainage system. For completeness i. Provide a Management and Maintenance Plan for the drainage system that includes clear plans showing all of the drainage network above and below ground, and identifies the responsibility of different parties for each component of the drainage network. ii. Include details of the necessary inspection regimes and maintenance frequencies. Thereafter the development shall be implemented and retained/maintained in accordance with these details for as long as the development remains in existence. REASON To ensure that surface water run-off is controlled and to ensure the development does not increase flood risk, in compliance with Policy EM6 of the Hillingdon Local Plan: Part 1 (2012), Policy DMEI 9 and DMEI 10 of the Hillingdon Local Plan Part 2 (2020), Policies SI 12 and SI 13 of the London Plan (2021) and the National Planning Policy Framework (2024). Item: 7 Location: 78 HighStreet Amendments/Additional Information: Officer Comments: A follow up comment has been received from a Local Ward Councillor post publication of the Committee report. The comments raised concerns regarding the current tenant of the shop and flat above who has resided at the property since 1985. The net impact from this development would impact the livelihood and home of the tenant. A negotiated settlement should have been arrived at rather than eviction. Members will be aware that the planning system can only take account of material planning considerations. Matters relating to private leases, the length of a tenancy, or contractual agreements between a landlord and tenant lie outside the scope of planning control. Such issues cannot be determinative in the assessment of the planning merits of the proposal. As set out in the “Principle of Development” section of the Committee Report (paragraphs 7.4–7.14), the application has been assessed on its planning merits, including the provision of additional residential units and the implications of the loss of ancillary storage space. The scheme retains a functioning retail unit at ground-floor level which remains viable in terms of floor area, servicing and layout.