Appeal 6008152

The appeal is allowed and planning permission is granted for a part single, part 2 storey rear extension following demolition of an existing rear extension at [site address] , Hounslow [postcode] in accordance with the terms of the application, [name]/2025/3606, 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 following approved plans: Location plan dated 2 December 2025, P.M.100, P.M.200, P.M.300, P.M.400C, P.M.500C, P.M.501C and P.M.600C.

The materials to be used in the construction of the external surfaces of the extension hereby permitted shall match those used in the existing building, in accordance with the details shown on approved drawing P.M.600C.

The new side facing first floor window hereby permitted shall be obscure glazed and non-opening unless the parts of the window which can be opened are more than 1.7 metres above the floor of the room in which the window is installed.

The main issues are the effects of the proposal on: (i) the character and appearance of the house and this part of [address]; and (ii) living conditions at neighbouring properties, in terms of effects on outlook and privacy.

[site address] is a modest 2 storey semi-detached house on a suburban street of similar buildings which have been extended in various ways at the back. The proposal is to replace a single storey lean-to rear extension with a larger 1 and 2 storey extension.

The Council’s Hounslow Character, Sustainability and Design Codes Supplementary Planning Document - Part A5 [name] (SPD) aims to ensure that the height, width and depth of rear extensions is proportionate and subordinate to the dimensions of the main house. For 2 storey or first floor rear extensions it sets a guideline of no more than 1⁄2 the width of the house.

The proposed 2 storey element would be more than 1⁄2 the width of the house but would be significantly less than full width. It would be out of public view and relatively small in scale, with a harmonious design, low height and shallow depth. It would be a subsidiary element of the overall building, fitting in well with the character and proportions of the house and avoiding any harm to the street scene despite the minor infringement of the SPD’s advice.

The Council raises no objection to the proposed flat roof single storey section, which would also be proportionate to the existing building. Although it would be deeper than normally advised by the SPD, it would sit next to an extension of a similar depth on the adjoining property.

I conclude that the proposed extension would not harm the character or appearance of the existing house and this part of [address]. Despite some minor conflicts with the detailed guidance of the SPD, the proposal accords in this respect with policies CC1, CC2 and SC7 of the London Borough of Hounslow Local Plan 2015-2030 (LP), which aim to secure high quality design and support residential extensions that maintain the character of the area.

The Council’s concern here is that the proposed first floor rear extension would be close the adjoining house, [address], due to its width being more than the SPD’s recommended maximum 1⁄2 width of the house. The Council says that this would cause a loss of outlook and an overbearing sense of enclosure to the residents of No 5. The only notable impact, however, would be on the outlook from a small, obscure glazed first floor rear window. It seems unlikely that this serves a habitable room and its outlook is already limited by the obscure glazing. I therefore see no objection there. The other rear first floor window at No 5 is set well away from the proposal and the adjacent ground floor windows are further to the rear.

No 9, to the other side, has ground and first floor windows on a rear wing facing towards No 7. The Council has not raised any issue about the impact on views from these windows, due to the distance between them and the proposed extension. The proposal does, however, include a new side facing first floor window that would give angled views into these windows. To prevent loss of privacy at No 9, the new window would need to be obscure glazed as set out in the proposed plans.

I note that no neighbours have objected. Despite a minor conflict with the guidance in the SPD, I conclude that the proposal would not harm living conditions at neighbouring properties. It also accords in this respect with LP policies CC1, CC2 and SC7, which additionally aim to minimise harm to neighbouring residents.

The appellant refers to a number of other appeal decisions. The circumstances in those cases appear to be significantly different. I have assessed this case on its own merits, in light of current policies.

I impose a condition specifying the relevant plans to provide certainty. A condition requiring the use of matching materials as proposed is needed to protect local character. For privacy, a further condition is needed to ensure that a side facing first floor window is obscure glazed as proposed.

I find that the proposal accords with the development plan. For the reasons set out above, and having regard to all other matters raised, I conclude that the appeal should succeed.