Appeal 6000207

The appeal is dismissed.

The Council raise no objections to the change of use of the property to a House in [name] (HMO), the single storey extensions, or the front facing rooflights. Its concerns relate to the proposed rear dormer roof extension. Therefore, the main issue is the effect of the proposed rear dormer roof extension on the character and appearance of the area.

The appeal site relates to a semi-detached property, comprising of four flats, located off [address]. Parking is provided to the front of the dwelling and there is a garden to the rear. Surrounding development comprises a mix of uses including residential dwellings, education facilities and a veterinary practice.

The proposed rear dormer would occupy almost the entire width of the main rear roof slope. It would then project outwards along the two-storey rear projection, occupying most of its width and part of its length. Given its considerable size, it would dominate the rear roofscape of the property. It would not be set down from the ridge of the roof, further exacerbating its dominance. It would fail to remain subservient to the host property and given its size, would somewhat unbalance the pair of semi-detached properties when viewed from the rear.

Whilst it is noted that the proposed dormer would be to the rear of the property, public views of the dormer are not a prerequisite for harm to occur and does not make up for the inappropriateness of the rear dormer’s scale. In any case, given its substantial scale and lack of set back from the side gable of the property, there would be some views of it from [address], in between neighbouring properties.

My attention has been drawn to an extant permission at the site, which granted planning permission for a rear dormer roof extension, amongst other things (Ref: 23/3602/FUL). This represents a fallback position which in my view, has a greater than a theoretical possibility of being carried out if this appeal is not allowed. However, the dormer approved under this scheme would have a reduced depth. In addition, it would be considerably set back from the side gable of the property, reducing its overall visual impact. As such, it would have a less harmful effect on the character and appearance of the area, in comparison to the appeal scheme. Whilst this scheme would also unbalance the pair of semi-detached properties, it would do so to a lesser extent given the smaller scale of the dormer. Given it would have a less harmful impact, I have afforded limited weight to this fallback position.

I am also aware of the allowed appeal at the site (Ref: APP/N5090/W/21/3271403). Although the Inspector found the scheme to be contrary to the Council’s Residential Design Guidance Supplementary Planning Document 2016 (SPD), they concluded that the proposal would not harm the character and appearance of the area. However, again the dormer allowed under this scheme was of a reduced depth. In allowing the scheme, the Inspector discussed the set in between the dormer and the gable to the side of the host roof. Again, this scheme would have a less harmful effect on the character and appearance of the area, compared to the appeal scheme before me. I have therefore afforded it limited weight in favour of the appeal.

I acknowledge that there is a somewhat similar dormer on the neighbouring property at [address] (No.99). However, the evidence suggests that the dormer at No.99 was constructed under permitted development rights, which is subject to a more limited set of considerations than a planning application. The appeal property would not benefit from permitted development rights in this way given its use as flats. In addition, No.99 is further set back from the road, reducing any visual impact on the street scene. In any instance, the presence of other similar development is not a reason, on its own, to allow unacceptable development. I have afforded limited weight in favour of the appeal to this consideration.

There are also other similar dormers on properties nearby and I accept that there is a degree of variation in roof form in the area. However, most appear to be of a smaller scale than the appeal proposal. In any case, I do not know the circumstances under which they were constructed or their status with regard to planning permission and therefore cannot draw any direct comparison with the proposal that would weigh in its favour. The presence of these does not overcome the harm that I have otherwise found.

For the reasons outlined above, the proposed rear dormer roof extension would result in unacceptable harm to the character and appearance of the area. This would be contrary to Policies CDH01 and CDH05 of the Barnet Local Plan (2025). Collectively, amongst other matters, these policies seek to promote high quality design and ensure that extensions are subordinate to the existing building in terms of size, scale and height. It would also be contrary to the SPD which seeks to ensure that, amongst other things, dormer roof extensions are sympathetic to the main roof of the house.

The appellant outlines how the existing four flats do not meet the current space standards and therefore could be considered to offer a substandard level of accommodation, whereas the scheme would ensure rooms which would meet the space standards. I am however not satisfied that this consideration would outweigh the harm identified.

I acknowledge that there may be a demand for HMOs, and less demand for family sized accommodation, in the area. The site is also located in an accessible location. These considerations however would not outweigh the harm to the character and appearance of the area. In any case, there is an extant approval on the site for HMO accommodation.

The lack of harm to neighbouring amenity, transport, fire safety or internal living conditions and lack of objection from environmental health are considered neutral factors and would not weight in favour of, nor against, the appeal.

The proposal would conflict with the development plan as a whole and there are no other considerations, including the provisions of the National Planning Policy Framework, which outweigh this finding. Therefore, for the reasons given above, I conclude that the appeal should be dismissed.