Two storey rear extension

Appeal Decision Site visit made on 18 March 2026 by J Bell-Williamson MA MRTPI an Inspector appointed by the Secretary of State Decision date: 31 March 2026 Appeal Ref: 6004474 86 Fortescue Road, Edgware HA8 0HN • 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 Valerian Haj against the decision of the Council of the London Borough of Barnet. • The application Ref is 25/4014/HSE. • The development proposed is a two storey rear extension. Decision 1. The appeal is dismissed. Main Issues 2. The main issues are whether the proposed extension would preserve or enhance the character or appearance of the Watling Estate Conservation Area in which the appeal property is located; and the effect on the living conditions of the occupiers of No 84 Fortescue Road, with regard to outlook. Reasons Watling Estate Conservation Area 3. The Watling Estate Conservation Area, located at Burnt Oak, covers a large area of predominantly residential properties. The Character Appraisal Statement for the area says that the character of Watling Estate is distinctive in terms of its layout, form, scale and building designs. 4. The layout is typical of Garden City planning and includes, amongst other arrangements, dwellings in small terraces of limited length, often symmetrical and balanced. These are seen in groups such as cul-de-sacs, around greens, recessed blocks and turned corners. Fortescue Road reflects this wider character, with terraces of two storey dwellings and a small green in front of the terrace of which No 86, an end-of-terrace property, is part. As such, the appeal property and the immediately surrounding area reflects the wider character and appearance of the conservation area and makes a positive contribution to it. 5. The Character Appraisal Statement also indicates that there are very few examples of unaltered buildings in the conservation area; most of the houses have been Appeal Decision 6004474 2 altered in some way and this tends to detract from their special character. However, within the street scene that includes the appeal property, substantive changes to the original built form of properties are not readily apparent. Most are well-proportioned and of uniform size and design. There is a single storey extension to the rear of No 82, but this is not readily apparent from the public realm. 6. The proposed two storey extension would be around half the width of the existing frontage of the dwelling with a lower roof height. It would, however, project across most of the width of the host dwelling’s garden seen from the road frontage and would bring built development much closer to No 88, the nearest property in the adjacent terrace. 7. The relatively generous gaps between terraces is a feature of this part of the conservation area, providing a sense of openness and visual relief between the built forms. By largely infilling the gap between the appeal property and No 88 across two storeys the proposal would result in a cramped form of development that would harmfully detract from the original layout of properties in the street scene. Due to the position of the proposed extension and despite the hedge to the road frontage, these effects would readily be seen from the public realm across No 86’s garden as well as from properties opposite. 8. The appellant draws attention to other examples of two storey extensions within the wider area. However, these are limited in number and do not reflect an established characteristic of the area such that they should be viewed as a positive precedent. There is an example of a side extension to No 73 within the same street scene, although this retains a visibly greater gap with the neighbouring end-of-terrace property than would be the case with the appeal proposal. Consequently, its effects are not directly comparable. 9. Therefore, for these reasons, the proposal would fail to preserve the character and appearance of the Watling Estate Conservation Area. The National Planning Policy Framework (the Framework) advises that when considering the impact of development on the significance of designated heritage assets, great weight should be given to their conservation1. Based on the above findings, I consider the harm to be less than substantial in this instance, but nevertheless of considerable importance and weight. 10. Under such circumstances, the Framework advises that this harm should be weighed against the public benefits of the proposal2. I acknowledge that the additional space created by the extension would provide an enhanced standard of accommodation and I note the appellant’s contention that the proposal will make effective use of land in accordance with an objective of the Framework. However, the harm to the designated asset is of considerable weight and, therefore, the proposal would not provide sufficient public benefits that would outweigh the harm that has been found. 11. I have had regard to the representations from interested parties in support of the proposal. However, these are not sufficient reason to set aside the above findings of harm to a designated heritage asset. 1 Paragraph 212. 2 Paragraph 215. Appeal Decision 6004474 3 12. Accordingly, for the reasons given, I conclude that the proposed extension would not preserve the character or appearance of the Watling Estate Conservation Area. Consequently, it is contrary to the following policies from the Barnet Local Plan 2021-2036 (2025): CDH01, which requires high quality design, including that proposals should respond to local character; CDH05 concerning extensions, which includes the requirement to maintain adequate spacing between surrounding buildings; and CDH08 concerning the effects of development on heritage assets, including conservation areas. It is also contrary to Policy D3 of the London Plan (2021), which requires development to respond to the quality and character of places; and to Policy HC1 of the same plan, also concerning the effects of development on heritage assets. 13. In reaching this conclusion I am particularly mindful of the statutory requirement that in exercising planning functions in conservation areas special attention shall be paid to the desirability of preserving or enhancing the character or appearance of that area3. Living conditions 14. No 84 adjoining the appeal property includes an upper floor window and ground floor door to provide access to the garden. The proposed extension would be four metres deep with a 1.8 metre first floor off-set from the shared boundary. 15. The Residential Design Guidance Supplementary Planning Document (SPD) indicates that the depth of a single storey rear extension normally considered acceptable for terraced properties is three metres; and that two storey rear extensions which are closer than two metres to a neighbouring boundary and project more than three metres in depth are not normally considered acceptable. 16. In this case the upper floor off-set, while marginally below the two metre distance from the boundary indicated in the SPD, would mitigate any harmful effects of the bulk of a two storey built form close to the neighbouring property. It would also prevent a harmful loss of daylight to the rear of No 84. 17. However, the depth of the extension, beyond the three metres that is normally acceptable for this type of dwelling, would result in some harmful effects. In particular, in combination with the existing extension to No 82, the overall depth of the extension would create an undue sense of enclosure to the occupiers of No 84, particularly in terms of reasonable use and enjoyment of the garden close to the rear of the dwelling. I recognise that the SPD is guidance to be applied judiciously, but these findings are based on the site inspection and appeal submissions as a whole. 18. I acknowledge that the current occupants of No 84 did not object to the proposal. However, given the permanent nature of the change proposed, the effects need to be considered in the long term, with regard to both current and future occupiers of the neighbouring property. 19. Therefore, based on these findings, I conclude that the proposal would have a materially harmful effect on the living conditions of the occupiers of No 84 Fortescue Road, with regard to outlook. As such, it is contrary to Policies CDH01 3 Section 72(1) of the Planning (Listed Buildings and Conservation Areas) Act 1990. Appeal Decision 6004474 4 and CDH05 of the Barnet Local Plan 2021-2036 and to Policy D3 of the London Plan, which include the requirement for development to provide a good standard of amenity. Conclusion 20. For the reasons given above it is concluded that the appeal should not succeed. J Bell-Williamson INSPECTOR