Appeal 3313447

The appeal is allowed and planning permission is granted for the erection of a rear roof and outrigger extension with two front roof windows at [site address] , Chiswick, Hounslow, London [postcode] in accordance with the terms of the application, Ref 00354/186/P1, dated 12 October 2022, subject to the following conditions:

The development hereby permitted shall begin no 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: 101 (P); 102 (P); 103 (P); 104 (P); 105 (P); 106 (PL); 107 (PL); 108 (PL); 109 (P); 110 (PL); and 111 (PL).

The recommendations in the [name] shall be implemented prior to the occupation of the development hereby permitted and thereby maintained in accordance with the report.

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.

Notwithstanding the description of development set out in the banner heading above, which is taken from the application form, it is clear from the plans and appeal form that the development comprises the erection of a rear roof and outrigger extension with two front roof windows. The Council dealt with the proposal on this basis and so shall [name] decision in paragraph 1 above reflects this approach.

The main issues are the effect of the proposed development on: • the character and appearance of the area; and • the living conditions of the occupiers of 184 and [address], with particular regard to outlook, sunlight and daylight.

The appeal site is located within a residential area on [address], close to its junction with [address]. It comprises a two-storey mid terraced dwelling with a tiled roof with side parapets. Two storey rear outriggers are a feature of houses in the terrace and the appeal property has one attached to a neighbouring outrigger at [address]. Several buildings on [address] and [address] have rear dormer extensions and there are also some extensions on top of outriggers so there is already little consistency to the nearby roofscape.

The rear extensions would be relatively large and bulky additions to the property. They would be contrary to the Council’s Residential Extension Guidelines Supplementary Planning Document 2017 (SPD) which seeks to resist additional storeys on top of original two storey outriggers and roof extensions that are as wide as the house, as well as including guidelines for setting in roof extensions from the roof ridge, eaves and sides.

However, other nearby properties in [address] already have similar extensions. There are also some existing large rear dormers on buildings close by on [address]. Therefore, although the adjoining properties do not have roof additions and there would be a loss of symmetry with them, the proposal would be consistent with the existing wider roofscape character of the area and would not be intrusive, out of scale or cause harm to the appearance of the host property, neighbouring dwellings or the wider locality. The extensions would be largely screened in views from [address] by a boundary fence and the existing outriggers at [address] so they would not harm the street scene, and, in any event, the scheme would not be harmful to the character and appearance of the area.

The proposed rooflights would only occupy a small proportion of the front roof and some other properties in the terrace already have similar front roof alterations. As a result, the rooflights would reflect the existing character of the roofscape in [address] and would not be an incongruous addition to the house.

Consequently, I conclude that the development would not harm the character and appearance of the area. It would comply with Policies CC1, CC2 and SC7 of the London Borough of Hounslow Local Plan 2015-2030 (the Local Plan). Together, these require extensions to sensitively respond to an area’s character, create distinctive and liveable places and have regard to the quality, character, materials and scale of the principal building. The proposal would also be in accordance with the National Planning Policy Framework (the Framework) which requires development to be sympathetic to local character.

Part of the rear extension is within the roofspace. Given that this would not protrude beyond the existing eaves line or above the ridge line, and would be set within the parapets, it would not cause undue harm to the outlook, sunlight and daylight of the occupiers of 184 and [address] (Nos 184 and 188).

Although the outrigger extension would be evident from the rear dwelling and side outrigger windows of No 184, there are already side windows which face each other in the existing outriggers of the two properties. Therefore, an additional higher-level window only visible at an angle from the rear and outrigger rooms at No 184 would not cause unacceptable additional overlooking or loss of outlook.

As the proposed outrigger extension would be located away from the mutual boundary, it would not adversely affect the amount of daylight to the rear rooms of No 184. Although the relative position of the extension is likely to cause some additional overshadowing to neighbouring windows in the mornings at certain times of the year, this would be limited given the separation distance between the existing windows and the extension, and its shorter projection than the original outrigger. Taking all these matters together, the proposal would not cause undue harm to sunlight in the rear rooms at No 184.

The outrigger extension would be close to the mutual boundary with No 188 and a small window on the first floor of this property which overlooks the two outriggers. Given that its projection would be less than the existing outrigger, the proposal would not cause unacceptable loss of outlook to the occupiers of No 188. Due to the relative orientation of the neighbouring property to the south of the appeal site, the proposal would not cause unacceptable loss of daylight and sunlight to the occupants of that house.

Overall, I conclude that the proposed development would not unacceptably harm the living conditions of the occupiers of Nos 184 and 188, with particular regard to outlook, sunlight and daylight. It would comply with Policies CC2 and SC7 of the Local Plan. Together, these require extensions to minimise harm to neighbouring residents by providing adequate outlook and ensuring sufficient sunlight and daylight to adjacent dwellings. The proposal would also be in accordance with the Framework which requires decisions to provide a high standard of amenity for existing users.

The extension would be constructed using bricks, tiles and felt/fiberglass and would be subject to control under building regulations. Furthermore, a [name] was submitted to the Council who considered that it complied with the London Plan policy requirements.

Given the size of the proposal, any disturbance from building work on neighbouring occupiers is likely to be small scale and temporary so a condition restricting working hours is not necessary. Furthermore, the appeal relates to an extension to an existing dwelling, and I have dealt with it on this basis. In addition, a neighbour is concerned about arrangements for notification of works or a party wall agreement, but this is a civil rather than a planning matter.

In addition to the standard time limit condition, I have imposed a condition requiring that the development is carried out in accordance with the approved plans. This is in the interest of certainty. To protect the character and appearance of the area, I have also imposed a condition requiring that the external materials used in the construction of the extension will match those of the existing building. A condition requiring implementation of the measures in the [name] is also necessary on public safety grounds.

For the reasons given, I conclude that the proposal would accord with the development plan and the Framework, and therefore the appeal is allowed.