Appeal 3344541

The appeal is dismissed.

The main issues are the effect of the appeal proposal on the character and appearance of the host property and the surrounding area and its effect on the living conditions of neighbouring occupiers.

The proposed extension would extend across the full width of the rear elevation of the host property at a depth of 6m, with a 3m high flat roof. Notwithstanding that the extension would not be visible from the street scene, the Council’s figures indicate that the ground floor area of the appeal property would be almost doubled, thereby demonstrating that the extension would not be subordinate. In my judgement its volume would dwarf the host dwelling and it would appear disproportionate and incongruous.

Furthermore, the proposed extension would extend well beyond the depth of the two neighbouring extensions. It would also exceed the maximum depth for extensions as set out in Policy DMHD 1. The depth and resulting mass of the extension would harm the character and appearance of the surrounding area.

There are extensions locally which are deeper than Policy DMDH 1 normally permits. However, proposals should be determined on their individual merits having regard to their context. The presence of larger extensions elsewhere is insufficient justification for allowing an otherwise harmful form of development.

I conclude that due to its depth, the scale and massing of the proposed extension would be unsympathetic to the design of the host dwelling and would harm its character and appearance as well as the visual amenities of the area. For these reasons the proposal conflicts with Policy BE1 of the Hillingdon Local Plan: [name] (2012) and [name] 11, DMHB 12 and DMHD 1 of the Hillingdon Local Plan: [name] - Development Management Policies (2020) (HLP2), Policies D3 and D4 of the London Plan (2021) and the design aspirations of the National Planning Policy Framework (the Framework).

The adjoining Nos 2 and [address] both have rear extensions. The main parties do not agree on their depths. But in any event, the proposed extension would extend considerably beyond the rear elevation of both neighbouring properties which contain glazed openings. From what I observed at the site visit and in the absence of any technical evidence to the contrary, I conclude that the combined depth and height of the proposed development would harm the living conditions of the occupiers of the neighbouring properties in respect of a loss of light and outlook and overshadowing. The absence of objections from the neighbouring occupiers does not affect this conclusion. Accordingly, the proposal is contrary to HLP2 [name] 11 and DMHD 1 and the Framework which, collectively and in summary, require new development to have a satisfactory relationship with adjoining occupiers.

For the reasons set out above and having regard to all other matters raised, the appeal is dismissed.