Appeal 3349123

The appeal is allowed and planning permission is granted for the excavation of a single storey basement extension with a front lightwell, erection of a single storey side extension (with alterations to the attached existing single storey rear and rear infill extension) and rear roof dormer extension and installation of one replacement front and three replacement rear roof lights and replacement first floor rear double doors/ windows to the house at [site address] , Chiswick, [postcode] in accordance with the terms of the application, [name]/2023/3451, subject to the conditions on the attached schedule.

The main issues are the effect of the proposal on a) the character and appearance of the host property and locality and b) living conditions of neighbours.

The appeal property is a sizeable two-storey semi-detached extended home with an ornate traditional front elevation and extension works to the rear. It sits in a stretch of broadly similar homes along this busy main road. The immediate locality is of established residential character and the streetscene is a pleasing one given the degree of frontage vegetation with relatively grand properties behind. The proposal is as described above.

The Council considers the planned extension works to be out of scale and character with the appeal property and surrounding dwellings.

The plans would see the depth of the single storey rear element increase to about 5 metres and it would merge with the proposed rear/side infill extension around the outrigger. However, this is a relatively frequent local characteristic.

I recognise that the scheme would project beyond the rear elevation of the abutting property’s adjoining glazed single storey rear infill extension but I would not read this as overly disruptive to the form of the pair of houses. The appeal property is a substantial structure with its original form, large dormer and ground floor extension. In this context the additional bulk sought would not appear over ambitious to my eye. A substantial garden would remain. The infill would be in a relativity subtle and unobtrusive form. Not dissimilar rear extensions do feature locally and there is a range of rear building lines and detached garden structures in the vicinity, some of appreciable scale.

The appeal property’s rear elevation is not open to wide views. The lower rear elevations between the semi-detached pair are already very different as things stand. Importantly the main bulk and form of the upper rear elevations, and more significantly the front elevations, would remain legible as a coherent and planned pairing notwithstanding the appeal scheme.

Hounslow Local Plan (LP) Policies CC1, CC2 and SC7, taken together and amongst other matters, call for development which relates to the form, scale and character of the original building and its surrounds. In all the circumstances I conclude that the appeal scheme would not conflict with these objectives.

The Council’s Residential Extension Guidelines (the REGs) includes similar objectives. The scheme would exceed its 3.65m depth guidance. However, this is guidance, stems from 2017, and cannot be expected to cover every eventuality. In this instance I am satisfied that aesthetic aims of that document would not be breached by the appeal scheme.

The Council is concerned that the proposed single storey rear and rear infill extensions, given depth, height, position close to boundaries, would seriously intrude on neighbours’ amenities through enclosure, loss of light and outlook

Whilst the structure would be higher than the present boundary wall it would be flat roofed in form, on level ground and not of undue height. It would project beyond the development on either side but I am not convinced that the relatively modest degree of extra length or bulk would be an undue imposition on amenity. Any loss of light would be very marginal. There would be a small degree of blinkering introduced to neighbours but considerable outlook would remain and gardens are relatively generous offering a sense of openness and an extensive viewing envelope for occupants. In summary, I would deem that this extra rear development would not unduly impact on the amenity of neighbours.

[name] CC2 and SC7 and the objectives of the REGs are also relevant under this issue in that taken together and amongst other matters they seek to secure development which would not be unduly harmful to residential amenity. Given the above I conclude that the proposal would not conflict with the policy aim of protecting living conditions or the parallel objectives of the REGs and that in this instance flexibility on its 3.65m depth guidance should apply. 2

The Council suggests the standard commencement condition and I agree with this and a condition that works are to be carried out in accordance with listed, approved, plans as this provides certainty. A condition on matching materials is reasonable in the interests of visual amenity. Restrictions on additional windows would be justified to safeguard residential amenity as would limitations on the use of the basement. Flood management measures should be covered in a planning condition in the interests of safety and amenity.

The suggested condition on wheel washing and highway cleansing is not practical on this small development site and dust emissions are controlled by other legislation, but I would agree that enrolment in the [name] would be appropriate in the interests of residential amenity.

For the reasons given above I conclude that the appeal proposal would not have unacceptable adverse effects on the character and appearance of the host property and locality or on the living conditions of neighbours. Accordingly, the appeal is allowed.

The development hereby approved shall be implemented no later than three years from the date of this decision.

The development hereby approved shall be carried out in accordance with the following approved plans and specifications: 011 ([name]), 23-CE-101 (Rev V2.0), Unreferenced Flood Risk Assessment & [name]: 27 June 2024, 012 ([name]), 013 ([name]) Received: 08 April 2024, 5559 (Issue No. 4) Received: 22 March 2024, 010 ([name]), 011 ([name]), 012 ([name]), 013 ([name]) Received: 20 March 2024, [name]: 21 November 2023, 001, 002, 003, 004, 005, 014 ([name]) Received: 10 November 2023.

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, unless otherwise shown on the approved plans.

No additional windows, doors or other glazed openings shall be formed in the house's altered single storey rear infill and rear extension, single storey side extension and rear roof dormer extension hereby approved.

The single storey basement extension hereby approved shall be constructed in accordance with flood management measures proposed in the submitted and 3 hereby approved Flood Risk Assessment/ [name] (Unreferenced) and [name] (Ref: 23-CE-101 (Rev V2.0)).

No development shall be carried out until such time as the person carrying out the work is a member of the [name] and its code of practice, and the details of the membership and contact details are clearly displayed on the site so that they can be easily read by members of the public.

The basement hereby permitted shall at no time be used or occupied as a separate dwelling independent of the main house and shall not be used as sleeping accommodation. 4