Appeal 3369522

The appeal is allowed and planning permission is granted for the erection of a single-storey rear extension at [site address] , Hounslow, [postcode] in accordance with the terms of the application, [name]/2025/0781, subject to the following conditions:

The development hereby permitted shall begin not later than 3 years from the date of this decision.

The development hereby permitted shall be carried out in accordance with the approved plans: [name] 2503DAM_HH:SH0 Rev 0, 2503DAM_ SH1 Rev 0, 2503DAM_ SH2 Rev 0, 2503DAM_ SH3 Rev 0, 2503DAM_ SH4 Rev 0, 2503DAM_ SH5 Rev 0, 2503DAM_ SH6 Rev 0, 2503DAM_ SH7 Rev 0, 2503DAM_ SH8 Rev 0, 2503DAM_ SH9 Rev 0, 2503DAM_ SH10 Rev 0, 2503DAM_ SH11 Rev 0 and 2503DAM_ SH12 Rev 0.

The materials to be used in the construction of the external surfaces of the development hereby permitted shall match those used in the existing building.

The main issue is the effect of the proposal upon the living conditions of neighbouring occupiers at [address] with particular regard to visual impact.

The appeal relates to a two-storey, detached dwelling facing [address] and occupying a corner plot with a side return boundary to [address] within a residential area. The property has previously been extended to its out-side with a single-storey side extension and which projects beyond the rear elevation of the original building. The proposal is to further extend at single-storey to the rear to a depth of 4m across the full width of the dwelling and to tie in with the existing side/rear extension.

Nos 15 and 17 are set on a staggered building line in relation to each other. According to an undisputed figure given by the Council, the rear elevation of the appeal property extends approximately 5.7m beyond the rear elevation of No 17 where it sits nearest to the shared common boundary. The proposal would add a further 4m depth at single-storey. The Council is concerned that the accumulated depth of building at No 15 would appear overbearing and intrusive when seen from No 17, creating an undue sense of enclosure.

[name] 15 and 17 are set away from the shared side boundary which separates both plots, which is marked by an approximate 1.8m high wall to the side of No [address] boarded fence along the remaining depth of the rear gardens, where the boundary is also lined with mature vegetation. Based upon observations during my site visit, both properties’ rear gardens, which are extensive in depth, appeared to be already significantly enclosed and fairly well secluded. The additional depth at No 15 would follow the alignment of the dwelling’s existing side elevation and would be set away from the boundary by the width of the existing side pedestrian access. Given this, and having regard also to the separation distance between the flanks of both dwellings, the extension’s single-storey height and proportionate scale, along with the existing degree of enclosure, I am not persuaded that the proposal would have any impact that would be significant or visually intrusive either in the outlook from within No 17, or when viewed from the neighbour’s expansive rear garden.

I note the depth of the extension would be compliant with the Council’s own guidance within The Hounslow Character, Sustainability and [name] A5 [name] (May 2024), which states that for detached houses, the maximum depth of a single-storey rear extension should be 4.25m. In light of this, and the context within which the proposed extension would be set, I am satisfied that there would be no harm to the living conditions at No 17. As such, there would be no conflict with Policies CC1, CC2 or SC7 of the Hounslow Local Plan 2015-2030 as far as between them they seek to ensure that new development responds to its context and minimises harm to neighbouring residents.

The appeal property is located within the Hanworth Park Conservation Area. The Council is satisfied that the proposed extension would be proportional and subordinate to the host property and of a high quality design that would be in-keeping within the surrounding area. I have no reason to disagree and share their view that there would be no harm to the character or appearance of No 15 or the wider area. It follows that the area’s significance as a heritage asset would be unaffected.

In addition to the standard time limit condition, a condition requiring the development to be carried out in accordance with the submitted plans is necessary for the avoidance of doubt and in the interests of proper planning. A condition requiring the materials used to match the existing is also necessary in the interests of safeguarding the character and appearance of the area.

The Council has suggested a condition for there to be no additional windows within the flank elevation of the extension. No such windows are proposed but, in any event, given the single-storey height of the extension, any side window would look directly at the existing boundary enclosure between Nos 15 and 17, which is a typical means of residential enclosure between neighbouring properties, without any intrusion towards No 17. No such control is therefore necessary.

For the reasons given above, the appeal is allowed.