21 Coppermill Road, Wraysbury, STAINES-UPON-THAMES, TW19 5NU

21 Coppermill Road, Wraysbury, STAINES-UPON-THAMES, TW19 5NU — Royal Borough of Windsor and Maidenhead — Appeal Decision Site visit made on 17 July 2025 by S Burch BSc MSc MRTPI an Inspector appointed by the Secretary of State Decision date: 19 August 2025 Appeal Ref: APP/T0355/W/25/3360734 21 Coppermill Road, Wraysbury, Staines, Windsor and Maidenhead TW19 5NU • The appeal is made under section 78 of the Town and Country Planning Act 1990 (as amended) against a refusal to grant planning permission. • The appeal is made by Mr Bhupinder Singh Mann against the decision of Royal Borough of Windsor and Maidenhead. • The application Ref is 24/01690. • The development proposed is the construction of 2no. dwellings, cycle storage and a new drop kerb following the demolition of the existing dwelling. Decision 1. The appeal is dismissed. Preliminary Matters 2. I have amended the description of development from the application form for reasons of clarity. The description I have used in the heading above matches that as provided on the decision notice. The appellant has confirmed in their statement of case that they have no objection to this description. 3.

21 Coppermill Road, Wraysbury, STAINES-UPON-THAMES, TW19 5NU — Royal Borough of Windsor and Maidenhead — Appeal Decision The Council have advised in its statement of case that since the determination of the application, they have reconsidered their approach to surface water flooding in flood zone 1 and consider that the matter could be dealt with via a condition, if the scheme was allowed. They have provided the wording of a condition to deal with this matter and advised that subject to the application of this condition, they would not pursue the second refusal reason. As I am dismissing the appeal for other reasons, I have not considered this matter further. 4. The site lies within the Green Belt, although it is within a ‘recognised settlement’ as defined in the Local Plan. The Council have not raised any concerns regarding the effect of the proposed development on the Green Belt. I see no reason to disagree with this. Main Issues 5. The main issues are: • the effect of the proposed development on the character and appearance of the area; and • whether the proposed development would secure Biodiversity Net Gain (BNG); and • whether the proposed development would comply with development plan policies in respect of climate change. https://www.gov.uk/planning-inspectorate

21 Coppermill Road, Wraysbury, STAINES-UPON-THAMES, TW19 5NU — Royal Borough of Windsor and Maidenhead — Appeal Decision Appeal Decision APP/T0355/W/25/3360734 Reasons Character and Appearance 6. The appeal site relates to a detached bungalow located on Coppermill Road. Surrounding development comprises both bungalows and two storey properties of varying sizes and styles. Properties tend to be set back from the highway, and benefit from relatively spacious plots with a degree of uniformity in plot size and shape. This creates a sense of spaciousness that positively contributes to the suburban character of the area. 7. The proposed development would result in the demolition of the existing dwelling, and subdivision of the plot to create a pair of semi-detached properties. Parking would be provided to the front of both properties. 8. The resultant plots and dwellings would be uncharacteristically small and narrow in comparison to surrounding development. Although there are other examples of semi-detached properties further along Coppermill Road, these are set on notably larger plots, of a similar size to the application site taken as a whole. As a result, the dwellings would appear cramped and contrived, contrasting with the surrounding pattern of development. 9. Substantial dormers are proposed on both the front and rear roof slopes.

21 Coppermill Road, Wraysbury, STAINES-UPON-THAMES, TW19 5NU — Royal Borough of Windsor and Maidenhead — Appeal Decision Principle 10.5 of the Royal Borough of Windsor & Maidenhead Borough Wide Design Guide (2020) (BWDG) states that dormers must be set back from the sides and ridgeline of the roof and not occupy more than half the width and depth of the roof slope. The proposed dormers would occupy more than half the depth of the roof slope and therefore fail to comply with this guidance. 10. As a result, the proposed dormers would dominate both the front and rear roof slopes, exacerbating the visual harm outlined above. The dormers would appear out of character with surrounding development and be unduly prominent within the street scene in the case of the front dormers. Whilst there are other examples of dormers in the area, generally these are of a much more modest scale and are not directly comparable. 11. The overall bulk, scale, height and massing would not be too dissimilar to the existing dwelling; however, the scheme seeks permission for two dwellings, in place of one dwelling. It is therefore not directly comparable to the existing situation on site and this consideration does not outweigh the harm identified above.

21 Coppermill Road, Wraysbury, STAINES-UPON-THAMES, TW19 5NU — Royal Borough of Windsor and Maidenhead — Appeal Decision Small gaps would be retained to the side of both dwellings, and this is somewhat comparable to existing arrangements. This however does not outweigh the harm I have identified. 12. The proposed dwellings would be readily visible from the street scene. Whilst the rear dormers would be less visible given their positioning on the rear roof slope, they are out of character with surrounding development for the reasons outlined above. Although the garden sizes may be greater that the Council’s standards, the overall plot sizes are not in keeping with the surrounding pattern of development. The appellant indicates that locally distinctive materials would be used to maintain local character. This would however not outweigh the harm identified. 13. In conclusion, the proposed development would be out of keeping with the surrounding pattern of development, constituting an overdevelopment of the site. https://www.gov.uk/planning-inspectorate 2

21 Coppermill Road, Wraysbury, STAINES-UPON-THAMES, TW19 5NU — Royal Borough of Windsor and Maidenhead — Appeal Decision Appeal Decision APP/T0355/W/25/3360734 The proposed dormers would dominate the roof slopes and exacerbate the visual harm outlined above. The scheme would therefore harm the character and appearance of the area, contrary to Policies QP1 and QP3 of the Royal Borough of Windsor & Maidenhead Borough Local Plan 2018-2033 (LP). Collectively these policies seek to ensure that new development positively contributes to the local character of an area. It would also not accord with Policies NP/HOU1 and NP/HOU2 of the Horton and Wraysbury Neighbourhood Plan (NP). Collectively, amongst other things, these policies seek to ensure that development respects the character of an area, including established plot widths. Biodiversity 14. Schedule 7A of the Town and Country Planning Act 1990 (as amended) (the Act) introduced a statutory framework for biodiversity net gain (BNG), and it applies to all planning applications for non-major development submitted on or after 2 April 2024. Under the statutory framework, subject to some exceptions, every grant of planning permission is deemed to have been granted subject to the Biodiversity Gain Condition (BGC), which requires that at least a 10% increase in biodiversity value is met.

21 Coppermill Road, Wraysbury, STAINES-UPON-THAMES, TW19 5NU — Royal Borough of Windsor and Maidenhead — Appeal Decision The proposal is advanced on the basis that, as a self-build dwelling, it is exempt from the BGC. 15. There is however conflicting evidence before me as to whether the scheme would be for self-build properties. The appellant suggests on the application form that the dwellings would be self-build. However, they have also stated that the dwellings would be market housing further down on the application form. The Council state that the submitted CIL form does not suggest there is self-build exemption. However, the appellant further stipulates that the proposal is for self-build dwellings in their statement of case. 16. Notwithstanding the above, the appeal has not been accompanied by a planning obligation which would secure the dwellings for this purpose. As such, the exemption would not be secured with any degree of certainty. A condition to secure the dwellings as self-build would fail to satisfy the tests in the National Planning Policy Framework (the Framework). The scheme would therefore be liable to provide BNG. 17. The submitted design and access statement and Ecological Impact Assessment outline various biodiversity measures such as bat boxes and planting.

21 Coppermill Road, Wraysbury, STAINES-UPON-THAMES, TW19 5NU — Royal Borough of Windsor and Maidenhead — Appeal Decision However, the details regarding these measures are relatively limited. The appeal has not been accompanied by the minimum information set out in Article 7 of the Town and Country Planning (Development Management Procedure) (England) Order 2015. In the absence of a completed metric calculation tool showing robust calculations of the pre-development biodiversity value of onsite habitat, and the other statutory minimum information requirements, the mandatory BNG requirements would not be met. 18. Policy NR2 of the LP is supported by the Royal Borough of Windsor & Maidenhead Sustainability Supplementary Planning Document (2024) (SPD) which states that, amongst other things, applications for all types and sizes of development will be required to provide the baseline ecological conditions of the site and biodiversity net gain calculation showing that at least 10% net gain will be met. As outlined previously, I am not satisfied by the evidence before me that this would be met. https://www.gov.uk/planning-inspectorate 3

21 Coppermill Road, Wraysbury, STAINES-UPON-THAMES, TW19 5NU — Royal Borough of Windsor and Maidenhead — Appeal Decision Appeal Decision APP/T0355/W/25/3360734 19. Policy NP/OE2 of the NP seeks to secure biodiversity enhancement, however, unlike the statutory provisions, it does not quantify the minimum amount of net gain that should be achieved. Given the reasonably modest scale of the proposal, and the size and characteristics of the site, it is reasonably likely that some biodiversity enhancements could be delivered on land under the control of the appellant. Furthermore, as outlined, the appellant has suggested various measures such as bat boxes and insect bricks. 20. Given the above, the proposal fails to adequately provide BNG and is contrary to Policy NR2 of the LP. Collectively, amongst other things, this policy seeks to ensure BNG. I am however satisfied that the scheme could meet the requirements of Policy NP/OE2 of the NP which seeks to ensure biodiversity enhancements. 21. The appellant has drawn my attention to an allowed appeal (Ref: APP/Y3940/W/23/3317252). They contend that the Inspector used a planning condition to secure self-build. I however do not agree that this was the case.

21 Coppermill Road, Wraysbury, STAINES-UPON-THAMES, TW19 5NU — Royal Borough of Windsor and Maidenhead — Appeal Decision Paragraph 40 of the appeal decision outlines how a unilateral undertaking (UU) pursuant to Section 106 of the Town and Country Planning Act 1990 (as amended) contained provisions relating to self-build and custom build housing. The Inspector further explains in paragraph 41 that the UU secures the self-build nature of the proposal. As outlined above, I am not satisfied that a condition can be used to secure the dwellings as self-build. Climate Change 22. Policy SP2 of the LP expects proposals to demonstrate how they have been designed to incorporate measures to adapt to and mitigate climate change and how they have been designed to maximise resistance and resilience to climate change. Part 3 of the policy explicitly requires developers to refer to the Sustainable Design and Construction Supplementary Planning Document or its successor documents, which include the Sustainability SPD. The SPD expects a Sustainability and Energy Statement, including calculations, demonstrating how the development would minimise emissions on site, to be submitted. It also requires development to provide a net-zero outcome. Any residual emissions should be offset by means of a financial contribution to the Council’s Carbon Offset Fund. 23.

21 Coppermill Road, Wraysbury, STAINES-UPON-THAMES, TW19 5NU — Royal Borough of Windsor and Maidenhead — Appeal Decision The submitted design and access statement states that a sustainability statement is attached, however this document does not appear to have been submitted with the application and is not before me. Various energy efficiency measures to reduce emissions, such as solar panels, double glazing and rainwater harvesting are outlined in the design and access statement, however this has not been supported by any calculations as required by the SPD. I am therefore not satisfied that the development has adequately demonstrated that emissions would be minimised on site. 24. The appellant outlines how the proposal introduces a number of measures as part of Sustainable Urban Drainage, satisfying criterion C and D of Policy SP2. The proposed landscaping does include numerous plants and vegetation, however the consultation response from the Lead Local Flood Authority highlights several concerns with the submitted flood risk assessment and sustainable drainage assessment. They explain how there is insufficient information which confirms how surface water would be managed on site and how the proposals would not https://www.gov.uk/planning-inspectorate 4

21 Coppermill Road, Wraysbury, STAINES-UPON-THAMES, TW19 5NU — Royal Borough of Windsor and Maidenhead — Appeal Decision Appeal Decision APP/T0355/W/25/3360734 increase surface water flood risk downstream of the site. This suggests that the proposal would not meet criteria D of Policy SP2. Nonetheless, even if I did accept that the scheme meets criterion C and D, I am not satisfied, based on the evidence before me, that the scheme has adequately demonstrated that emissions would be minimised on site. 25. I am not satisfied that the submission of a post development energy statement would overcome the harm identified. In any case, the policy requires proposals to demonstrate how they have been designed to incorporate measures to mitigate climate change and any residual emissions to be offset by means of a financial contribution. 26. Therefore, on the basis of the evidence provided, I cannot conclude that the proposed development would be designed to maximise resistance and resilience to climate change or provide a net zero outcome. There is no mechanism before me to ensure a financial contribution to offset residual emissions. The scheme is therefore contrary to Policy SP2 of the LP. Other Matters 27.

21 Coppermill Road, Wraysbury, STAINES-UPON-THAMES, TW19 5NU — Royal Borough of Windsor and Maidenhead — Appeal Decision The proposed dwellings may not encroach on a 45-degree line from neighbouring windows and the style of the dwellings may be in keeping with surrounding development. They may provide cycle storage and changing/drying facilities. The appellant advises that they would be built in accordance with building regulation standards to ensure insulation and access. They may also be located away from pollution and sensitive uses and construction may only occur during normal working hours, utilising low noise building methods. These are however considered to be neutral factors and would not weigh in favour of, nor against the appeal. Planning Balance and Conclusion 28. The evidence before me outlines that the Council can only demonstrate a 4.47 year supply of deliverable housing sites. This is a modest shortfall. In these circumstances paragraph 11d) of the Framework is engaged. There is nothing before me to suggest that there are any policies in the Framework that protect areas or assets of particular importance that provide a strong reason for refusing the development under paragraph 11d)(i). 29.

21 Coppermill Road, Wraysbury, STAINES-UPON-THAMES, TW19 5NU — Royal Borough of Windsor and Maidenhead — Appeal Decision Therefore, the balance in paragraph 11d(ii) applies such that planning permission should be granted unless any adverse impacts of doing so would significantly and demonstrably outweigh the benefits when assessed against the policies in the Framework taken as a whole. 30. The scheme would provide housing in an accessible location. It would also make efficient use of a brownfield site. The dwellings may incorporate security and energy efficiency measures such as solar panels and composting facilities. Landscaping is proposed to the front and rear and the appellant has advised that responsibly sourced building materials would be sourced from within 30 miles of the site, reducing transport and energy costs. Lighting used may also be designed to reduce light pollution and the dwellings may meet part M of the building regulations to provide accessible and adaptable dwellings. However, given the relatively small scale of development I attribute these benefits limited weight. https://www.gov.uk/planning-inspectorate 5

21 Coppermill Road, Wraysbury, STAINES-UPON-THAMES, TW19 5NU — Royal Borough of Windsor and Maidenhead — Appeal Decision Appeal Decision APP/T0355/W/25/3360734 31. Accordingly, I find that the adverse impacts arising from the development in terms of harm to the character and appearance of the area, its failure to provide BNG and maximise its contribution to climate change adaption and mitigation would significantly and demonstrably outweigh the limited weight attributed to the benefits when assessed against the policies in the Framework taken as a whole. The presumption in favour of sustainable development does not apply in these circumstances. 32. Planning law requires that applications for planning permission be determined in accordance with the development plan, unless material considerations indicate otherwise. There are no other considerations, including the provisions of the Framework, which outweigh this finding. Therefore, for the reasons given above I conclude that the appeal should be dismissed.

21 Coppermill Road, Wraysbury, STAINES-UPON-THAMES, TW19 5NU — Royal Borough of Windsor and Maidenhead — S Burch INSPECTOR https://www.gov.uk/planning-inspectorate 6