Appeal 3361448

The appeal is dismissed.

The main issue in the appeal is the effect of the proposal on the character and appearance of the host dwelling and surrounding area.

The site comprises a two-storey semi-detached dwelling located on the southern side of [address] in a predominantly residential area. The property incorporates a two-storey rear outrigger on its eastern side adjacent to no.[address]. At ground floor level there is a single storey lean-to extension on the southern end of the outrigger, and a single storey side extension on the west side of the property. At the time of my site visit, building works were being carried out and a third storey was in the course of construction on the rear outrigger.

The semi-pair is no.[address]. The neighbouring house to the west is no.[address] which is a detached two storey house with a rear garden. This house stands on the corner of [address] and [address]. Much of the rear of the appeal site building can be seen from the public realm in [address].

The proposed development consists of a single storey rear extension which would be located to the rear of the side extension and to the rear of the main rear elevation of the dwelling. It would infill the area between the outrigger/lean-to extension and the common boundary with no.[address]. It would not extend beyond the rear (south) wall of the lean-to extension.

The Hounslow Character, Sustainability and Design Codes Supplementary Planning Document, A5 [name] (2024) advises that for single storey rear extensions the Council has set maximum depths for different house types, and for semi-detached houses that is 3.65m. The proposed extension would cumulatively have a depth of about 6.6m from the main rear elevation of the property. The guidelines on infill extensions are more flexible but indicate that a height of no more than 2m is typically appropriate and in this case the proposed height is 2.9m up to a flat roof.

Whilst the proposal is on the west side of the appeal site plot (as opposed to on the common boundary with no.28), it would add bulk and mass to the host dwelling such that it would fail to appear subordinate to the host dwelling. It would also be visible from [address] above the common boundary wall with no.30 and these views would give a detrimental overdeveloped appearance to the area.

Local Plan policies CC1, CC2 and SC7 require proposals and to conserve and enhance the character of an area so that they respond sensitively to any local architectural vernacular. In my view, the proposal would also detract from an appreciation of the original design of the dwelling which is one of back-to-back rear outriggers as part of semi-detached dwellings with generally open areas facing the outriggers. I do not consider that the extension, given its particular proposed dimensions, would complement the original building.

Consequently, I consider that the proposal would result in unacceptable harm to the character and appearance of the host dwelling and the surrounding area. It would be contrary to policies CC1, CC2 and SC7 of the Hounslow Local Plan 2015-2030 (adopted 2015) and the [name], Sustainability and Design Codes Supplementary Planning Document, A5 [name] (2024).

Having considered all representations made, for the reasons given above, I dismiss the appeal. [name].C.