Mansard roof extension to existing dwellinghouse

Appeal Decision Site visit made on 10 February 2025 by N Unwin BSc (Hons) MSc MRTPI an Inspector appointed by the Secretary of State Decision date: 6th March 2025 Appeal Ref: APP/N5660/D/24/3356164 246A Norwood Road, Lambeth, London SE27 9AJ • 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 J Gluck against the decision of the Council of the London Borough of Lambeth. • The application Ref is 24/02530/FUL. • The development proposed is described as: Mansard roof extension to existing dwellinghouse. Decision 1. The appeal is dismissed. Preliminary Matters 2. During the course of the appeal the National Planning Policy Framework December 2024 was revised. There are no substantive changes relevant to the main issues in the appeal before me. 3. As part of the appeal the appellant submitted additional daylight and sunlight information. The Council were provided with an opportunity to comment on this. 4. Both parties refer to the adjacent property as 2A/2B Ullswater Road. Based on the plans of approval 02/00330/FUL submitted by the appellant and observations made during my site visit, I consider that 2B Ullswater Road represents the first- floor accommodation. Main Issues 5. The main issues are: • the effect of the proposal on the living conditions of the occupiers of 2B Ullswater Road with specific regard to outlook, and 9 and 11 Ulverston Road with specific regard to outlook, and levels of daylight and sunlight; and • whether the proposal would provide acceptable outlook for future occupiers. Reasons Living conditions of neighbouring occupiers 6. 2B Ullswater Road (No 2B) is an elongated building with two first-floor windows within the elevation closest to the appeal property with the separation distance between these two buildings severely restricted. Based on the plans submitted by the appellant, these first-floor windows appear to serve two bedrooms. Given the Appeal Decision APP/N5660/D/24/3356164 2 single storey scale of the appeal property, these two first-floor windows of No 2B provide good levels of outlook for occupiers. 7. The proposed mansard roof would be of a similar height to No 2B, extending across almost the entire length of its northern elevation. The top of the mansard roof would project above the top of the aforementioned first-floor windows, extending either side of them. When combined with the exceptionally close relationship of these buildings, the proposal would completely dominate views from the two first-floor windows of No 2B, having a detrimental impact on the outlook of occupiers. Further, one of these windows represents the only opening to one of the first-floor bedrooms of No 2B, elevating its importance to the outlook of its occupiers and intensifying the harm of the proposal in this respect. 8. 9 Ulverston Road (No 9) and 11 Ulverston Road (No 11) form part of a terrace of properties with small rear gardens which abut the appeal site, proving a limited separation distance between their rear elevations and the appeal property. The single storey nature of the appeal dwelling restricts its prominence when viewed from the rear garden areas of No’s 9 and 11, with their occupants benefiting from good levels of outlook across the appeal site. 9. The proposal would result in a significant increase in the height of the appeal property, with the use of a mansard roof substantially increasing its form when viewed from the rear gardens of No’s 9 and 11. When combined with its close proximity, the proposal would appear dominant and overbearing when viewed from the garden areas of No’s 9 and 11, diminishing the existing open outlook in this direction. As such, the proposal would have an unacceptable impact on the outlook of the occupiers of these properties. 10. The appellant raises the lawfulness of No 2B. Even if this property were unlawful, this would not outweigh the harm identified above to the living conditions of the occupiers of No’s 9 and 11. 11. The daylight and sunlight assessment accompanying the application demonstrates that any impact on levels of daylight and sunlight on the garden areas of No’s 9 and 11 would be negligible which the Council do not dispute. A subsequent assessment of the effect of the proposal on levels of daylight and sunlight on the rear windows of No’s 9 and 11 was submitted with the appeal, concluding that any impact would be negligible in this respect. I have no reason to disagree. Therefore, the proposal would be acceptable with regard to its effect on levels of daylight and sunlight of the occupiers of No’s 9 and 11. 12. I therefore conclude that the proposed development would not unduly affect the levels of daylight or sunlight for the occupiers of No’s 9 or 11. Nonetheless, it would unacceptably harm the living conditions of the occupiers of No’s 9 and 11 and No 2B with regard to outlook. The proposal would therefore conflict with the relevant provision of Policy Q2 of the Lambeth Local Plan 2020–2035 (2021) (Local Plan), which requires development to not unacceptably compromise the living conditions of adjoining occupiers. Living conditions of future occupiers 13. The appeal property adjoins a derelict site. The proposal would include two first- floor windows facing the derelict site, representing the only non-obscure glazed Appeal Decision APP/N5660/D/24/3356164 3 windows to a living/ dining area, providing future occupiers with a good level of outlook. 14. Policy Q7 of the Local Plan generally supports new development provided it does not prejudice the optimum future development of adjoining plots. The Council considers that the proposed first-floor windows offering views over the derelict site would compromise its future development and would therefore be required to be obscure glazed. It goes on to say that should these windows be obscure glazed, the proposal would not achieve an acceptable level of outlook for future occupiers of the proposed living/ dining area. 15. The first-floor nature of the proposed non-obscure glazed windows would not prevent the development of the derelict site at ground floor level. Furthermore, the derelict site shares a similarly confined relationship to the properties adjoining Ulverston Road as the appeal site and I therefore consider it unlikely that development above ground floor level would be practicable. As such, these windows would not be required to be obscure glazed, securing adequate outlook for future occupiers. 16. I therefore conclude that the proposal would provide an acceptable standard of outlook for future occupiers in accordance with the relevant provisions of Policy Q2 of the Local Plan which requires new development to provide adequate outlook. Other Matters 17. I acknowledge that the existing floor space of the appeal property may be below the minimum gross internal floor area for a one bedroom, one storey dwelling set out within the Technical housing standards – nationally described space standard (2015) and that the proposal would represent an increase in floor space benefiting occupants, to which I attach moderate weight. I take the same view in respect of the additional light to the dwelling the proposal would provide. Nonetheless, these benefits do not outweigh the harm to the living conditions of the occupiers of No’s 9 and 11 and No 2B identified above. 18. Third party comments raise the effect of the proposal on privacy and noise in respect of the occupiers of No 11. The Council have assessed this, raising no concern and from all of the information before me, including my own observations at my site visit, I have no reason to disagree with that assessment. Conclusion 19. I find that the proposal would provide an acceptable standard of outlook for future occupiers and not unduly affect the levels of daylight and sunlight of the occupiers of No’s 9 and 11. Nevertheless, this does not outweigh the harm I have identified to the living conditions of the occupiers of No’s 9 and 11 and No 2B with regard to outlook. Accordingly, the appeal is dismissed. N Unwin INSPECTOR