Appeal 3339246

The appeal is dismissed.

The main issue is the effect of the proposal on the living conditions for adjoining occupiers as regards outlook.

The appeal dwelling is one half of a semi-detached pair with No. [address]. The property has a dormer extension that covers the full rear roof plane and a flat roof single storey rear extension to about half of its width on the side closest to No. 11. Planning permission ref. 22/3222/DD01 was granted in May 2023 for the demolition of this extension and a rear bay window and the erection of a full width single storey rear extension of a depth of 4m and with a part flat/part hipped roof.

Although the appeal scheme is a fresh proposal, it effectively seeks to amend the earlier permission with a proposal for a flat roof over the full width of the extension at a height of 3.4m. Because the extension would extend to the actual boundary with No. 15, the outlook for existing and any future occupiers of that dwelling along the first 4m of the boundary would inevitably be restricted from the bay window and the part of the garden nearest the house.

As regards the height, the proposed 3.39m is significantly in excess of the 2.2m stipulated in the Council’s house extensions guidance as a maximum in a situation where the length would be more than 3.5m – in this case 0.5m greater. And although this guidance says that the final test of acceptability depends on the specific circumstances of the site, in this instance to the rear of No. 15 there is a box bay-window with two glazed side panels and three rear panels.

The officer’s report specifically refers to a height of no more than the guidance figure of 2.2m being needed to ‘mitigate detrimental impact on neighbours such as sense of enclosure or overbearing’. In this context, I consider that only the outlook from the living area through the side panel closest to No. 15 on the other side of the property would avoid being significantly affected by a wall of the height proposed on the boundary.

Furthermore, in the perception of whether a building would be overbearing or result in undue sense of enclosure, I take the view that a flat roof at the top of a fairly high wall has a particularly egregious impact compared to a roof sloping away that gradually increases in height to an apex. This is because it reinforces or conveys a perception of the building being bulky rather than having a sensitive design.

I also saw on my visit that the plot widths and lengths of the semi-detached pair are fairly limited. In these circumstances, it is reasonable to assume that all of No. 15’s garden, but particularly the area closest to the rear wall, would be regularly used for amenity purposes.

I have noted and do not dispute the comment in the grounds of appeal that the effect on sunlight would not be such as to warrant a refusal of the application. Nonetheless, as semi-detached houses it is important that development proposals for one dwelling have regard to the inevitable constraints on the other half of the pair so as to maintain an acceptable outlook for its neighbour.

In my assessment, the revision now proposed to the approved scheme would restrict outlook and significantly increase enclosure. This would be a more harmful effect on No. 15 than the amount of benefit that would accrue to No.

The proposal would be in harmful conflict with Policy LP8 of the Richmond Local Plan 2018; the [address] Extensions guidance, and paragraph 135f) of Government policy in the National Planning Policy Framework 2023.

The appeal is dismissed accordingly.