Retention of hip to gable roof extension with 2 front rooflights, rear dormer with juliette balcony, ground floor rear extension, front porch and rear garden outbuilding. Proposed alteration to reduce height of existing rear dormer of dwellinghouse

Appeal Decision Site visit made on 5 August 2026 By G Powys Jones FRTPI an Inspector appointed by the Secretary of State Decision date: 14 August 2026 Appeal Ref: 6011399 37 Grove Crescent, London, NW9 0LS • 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 Ms Christine Boateng against the decision of Brent Council. • The application Ref is 26/0129. • The development is described as retention of hip to gable roof extension with 2 front rooflights, rear dormer with juliette balcony, ground floor rear extension, front porch and rear garden outbuilding. Proposed alteration to reduce height of existing rear dormer of dwellinghouse. Decision 1. The appeal is allowed, and planning permission is granted for retention of hip to gable roof extension with 2 front rooflights, rear dormer with Juliette balcony, ground floor rear extension, front porch and rear garden outbuilding at 37 Grove Crescent, London, NW9 0LS in accordance with the terms of application Ref 26/0129, subject to the following condition: The outbuilding hereby permitted shall not be used other than for purposes incidental to the dwelling known as 37 Grove Crescent. Preliminary and procedural matters 2. The development is comprised of several elements, which are all substantially complete. However, the submitted plans show a proposal to slightly reduce the height of the as-built rear dormer, and it was on this basis that the application was considered by the Council. The appellant, however, has requested that I consider the acceptability of the dormer as it stands. 3. Accordingly, the appellant wishes to retain all which has been built. I shall therefore treat the appeal as if the original application had been made under section 73A of the Act1. 4. The Council has signified in the officer report that it has no objection to the roof alterations carried out2 or to the front porch. Judging from what I saw I have no reason to object either. 5. When visiting the site officers carried out detailed measurements of the various built forms, and their accuracy are not contested by the appellant. It is clear from the officer report that the measurements have been considered relevant in the 1 The Town & Country Planning Act 1990 (as amended). 2 Subject to the dormer’s proposed height reduction Appeal Decision 6011399 2 context of the Council’s Supplementary Planning Document on Residential Extensions and Alterations (SPD). This is a recent document, published last year, and is a material consideration attracting due weight. Its introductory paragraphs underline its role as guidance in the context of development plan policy. This is my understanding of the primary role of SPDs such as this. Main Issues 6. These are: (a) the effect of the single storey rear extension and dormer on the character and appearance of the host property and its surroundings, and (b) the effect of the single storey extension and outbuilding on neighbouring living conditions. Reasons Character & appearance 7. The host property is a semi-detached dwelling set in a residential area displaying distinct suburban characteristics. The single storey rear extension’s slab is slightly elevated on account of the sloping nature of the plot, and the extension is longer than the length advised in the SPD by around 0.6m. Nevertheless, it appeared to me to be of an acceptable design and subservient in scale to that of the host property. I did not therefore find its visual relationship to the dwelling to be inappropriate. Having regard to its position at the rear of the house the extension has no harmful impact on the public realm. 8. As to the dormer, given the nature of neighbouring similar development, it would make no material difference to local visual amenity in my opinion if it were maintained at its existing height, rather than being slightly reduced in height as originally proposed. 9. In conclusion, I find that neither the rear extension nor dormer, as built, have proved harmful to the character and appearance of the host property and surroundings. Accordingly, no conflict arises with the provisions of policy DMP1 of the Brent Local Plan (LP) requiring development to be of a design complementing the locality. Living conditions 10. The Council’s concerns on the rear extension relate to the alleged effect on the occupants of 39 Grove Crescent. The Council considers that the combination of the extension’s length, height and position on the common boundary would result in the extension being perceived by No 39’s occupants as overbearing. The Council also considers that its residents would suffer loss of light. 11. No 39 Grove Crescent has a relatively modest ground floor extension which the Council has calculated to be 2.68m deep. This means that the appellant’s extension projects beyond that of its neighbour by under 4m, which would be the length of extension perceived by No 39’s occupants. This appears to me to be of a reasonable and acceptable length when viewed from No 39. 12. It’s height on the boundary is over a metre higher than advised in the SPD. In its assessment the Council appears not to have taken account of No 39’s outbuilding, which adjoins its rear extension at a height equivalent to the top of the extension’s rear window. This, it appeared to me, to be more intrusive than the appellant’s and, Appeal Decision 6011399 3 on account of its position in relation to the daily path of the sun, far more likely to affect light to No 39. I note too that the Council did not provide calculations in support of its allegation on loss of light, and has not confirmed whether the glazing in No 39’s rear extension serves a habitable room. In my subjective judgment, having regard to that seen, and having regard to pre-existing site conditions, the extension has not caused material harm to No 39’s residents. 13. As to the outbuilding, the Council accepts, taking account of the garden’s size and the proliferation of other outbuildings in the locality, that it could not reasonably object to its size. However, having regard to the SPD’s empirical guidance, it considers its height close to the boundary with No 35 to be such that the outbuilding would have an overbearing effect on its residents. 14. Nos 35 & 37 rear gardens are relatively lengthy, and the outbuilding is sited well away from No 35’s rear elevation such to have no impact on its internal environment. Taking account of its distance from the side boundary, the building is about 0.5m higher than advised in the SPD, a height making little or no difference to the building’s perception from No 37’s rear garden than if it had been built to accord with the maximum height recommended in the SPD. 15. Having regard to that seen at my visit the Council’s objections seem to be based more on a strict, if not slavish adherence to the SPDs empirical content rather than on a considered judgment, having regard to site conditions, utilizing the SPD as guidance, as intended. I do not consider, on balance, that the objections in respect of either the extension or outbuilding, to be justified. 16. Although not conclusive in my considerations, neither of the neighbours either side objected on being consulted. They were invited to comment, not on proposals, but on account of what had been built. The Council’s objections are largely based on the assumed neighbouring residents’ perceptions of the development as implemented, but there is no evidence before me that the Council’s objections are supported by those whose amenities they seek to protect. 17. In conclusion, I find that neither the rear extension nor the outbuilding, as built, have harmed neighbouring living conditions. Accordingly, no conflict arises with those provisions of policy DMP1 of the Brent Local Plan (LP) requiring development to provide high levels of internal and external amenity. Conditions 18. Since the development is substantially complete the imposition of the usual standard conditions is unnecessary. However, in the interests of clarity and certainty, a condition is imposed in relation to the future use of the outbuilding. Other matters 19. I have taken account of the references made to the planning history of the site, other development plan policies and to the National Planning Policy Framework. However, no other matter raised is of such strength or significance as to outweigh the considerations leading me to my conclusions. G Powys Jones INSPECTOR