Appeal 3283894

The appeal is dismissed.

In its decision the Council refers to, amongst other things, Policy GB1 of the Hounslow Local Plan 2015 - 2020 (2015) (‘HLP’). However, in the appeal questionnaire it confirms that the site is not within the Green Belt, which according to the delegated officer report lies to the west and to the north. Consequently, that policy is not relevant to this appeal, and it has not been necessary for me to consider the proposal’s impact on the Green Belt.

The main issue is the effect of the proposed development on the character and appearance of the host property and the area.

In general terms, [name] CC1 and CC2 require development proposals to respond to the urban context and to the site and its characteristics. HLP Policy SC7 addresses residential extensions. It expects proposals not to harm the existing character and appearance of the building and its context, to complement the original building, be subordinate, and to not over develop the site in terms of mass and density. It also requires regard to be had to the Council’s Residential Extension Guidelines Supplementary Planning Document 2017 (‘SPD’).

Section 4 of the SPD states that side extensions should normally be set back from the main front wall of the house, particularly at first floor level, and should allow the original proportions of the building to remain the prominent feature. It continues that the height and width of side extensions should be proportionate and subordinate to the dimensions of the main house; that the width should be less than half the width of the main house; and that the roof should be set down from the roof of the original house by at least half a metre.

Finally, it also states that an annexe which provides accommodation for a relative must not have a separate entrance, and must not be designed in a manner so that it is capable of being used as a separate dwelling.

Blenheim is a very substantial two storey detached property, with single and two storey rear projections. Its walls are mostly finished in cream coloured render. Viewed from the front, it has a single storey extension to one side, which is where the proposed two storey annexe would be located.

The ridge of the proposed annexe would be below that of the principal building, it would have a similar hipped roof form, and the scheme would be faced in matching materials.

However, whilst the SPD includes illustrations of acceptable two storey extensions, with matching eaves heights as would be the case here, this one would be broadly level with the front face of the host at both ground and first floor level. Moreover, its two storey bay window would project significantly forward of the host.

As a result, and given that it would only be attached to the host by a low-level link, and that it would have a rear entrance separate from the host property, the scheme would take on the broad form, character and appearance of a separate dwelling. Viewed as a whole, the proposed annexe would have a very significant scale and bulk, and it would not appear subordinate to the host property.

The nearby area, which includes fields, an historic pub, and commercial development close to Heathrow airport, has a very mixed character. Consequently, whilst the scheme would be visible from [site address] , it would cause only limited harm to the character and appearance of the wider area, but for the reasons above, it would cause more significant harm to the host property. It would therefore conflict with [name] CC1, CC2 and SC7, along with the guidance in the SPD.

The scheme’s benefits to the appellant and his growing family as a result of their need for additional space do not outweigh the harm that it would cause. For the above reasons, it would conflict with the development plan when considered as a whole, and the appeal is therefore dismissed.