Appeal 6007430

The appeal is dismissed insofar as it relates to the erection of first floor roof extension. The appeal is allowed insofar as it relates to the erection of a single storey rear extension with roof lantern at [site address] , Orpington, [postcode] in accordance with the terms of the application, Ref 26/00168/HPA and the plans submitted with it, so far as relevant to that part of the development hereby permitted and 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 and documents, in so far as they relate to the single storey rear extension hereby permitted: Location Plan, Drawing 1, Drawing 2 and the application form.

The main issue is the effect of the proposal on the character and appearance of the pair of dwellings, the street scene and the Knoll Area if Special Residential Character, (ASRC).

The ARCS, which includes [address], is characterised by uniformly sited detached and semi-detached family houses from a limited palette of designs and materials. Typically, they have fully hipped roofs which add to the sense of space between individual buildings above pairs of pitched roof garages to the sides of the dwellings. The dwellings also have two storey front bay features with gable roofs and some of the dwellings have front dormer windows set within front catslide roof-slopes.

Within the area some of the dwellings have first floor side extensions above the garages and/or roof extensions, which have blended into the street scene with varying degrees of success. There are a number of prominent bulky additions to the side and rear roof slopes that have detracted from the form and balance of some of the pairs of semi-detached houses and the street scene as a whole. Rather than set a precedent, they highlight the need to assess each scheme on its individual merits and in accordance with the prevailing planning policies.

The appeal dwelling comprises one of a pair of symmetrically designed houses with a fully hipped roof; centrally positioned front projections under a hipped roof, with flat roofed bay windows at ground floor level. The dwellings also have narrow front projecting porches with fully hipped roofs.

Consistent with other dwellings along [address] the pair of dwellings have garages located to the side. However, the garage to the side of the appeal dwelling has been extended. It projects up to the front wall of the host dwelling and beyond the adjacent rear wall of the dwelling. It does however retain a front gable which matches that of the adjacent dwelling at No.34. The adjoining dwelling at No.30 has a two storey side extension which is set back from the front of the house and has a lower ridge line and matching eaves line. To the front of this extension is a garage which has a hipped roof and projects forward of the front building line of the pair of dwellings. These changes have detracted from the symmetry of the original pair of dwellings.

Collectively and amongst other things policies 6, 8 and 37 of the London Borough of Bromley Local Plan 2019 (BLP), policy D3 of the London Plan and paragraph 135 of the National Planning Policy Framework (the Framework), seek to ensure that new developments are of a high standard of design and layout. They should complement the adjacent buildings and areas and positively contribute to the street scene. Developments should also optimise the capacity of sites through a design-led approach. Residential extensions should respect and complement the host building and be compatible with the surrounding area. The gaps between buildings should be respected or maintained where they contribute to the street scene. A minimum of one metre should be retained between two storey extensions and side boundaries for the full height and depth of the building. Where greater separation distances exist, wider gaps are expected.

BLP Policy 44 requires development within ASRC’s to respect, enhance and strengthen their special and distinctive qualities.

The proposed rear extension would be visually uncluttered and would respect the proportions and form of the existing rear elevation and would also be comparable in depth and width to the rear extension at No.30. As indicated on the submitted drawings and in the application form the window detailing and external materials would match those of the host dwelling. For these reasons the proposed rear extension would blend in appropriately with the host dwelling and the pair of dwellings.

The proposed side extension would have a hipped roof that would be set down from the ridge line of the host dwelling. In this respect, it would reflect the existing side extension at No.30. However, the proposed side extension would project close to the front building line of the host dwelling; would have a lower eaves line than the host dwelling; and would include a dormer window. The roof of the proposed dormer window would be out of alignment with the garage roof to the front of it. For these reasons the relationship between the dormer window and the existing garage and porch would appear cluttered and poorly proportioned. The side extension would also disrupt further rather than restore the symmetry of the pair of semi-detached houses.

I am less concerned regarding the relationship with No.36. Whilst a gap of one metre would not be provided at ground floor level the proposed first floor extension would maintain a gap of one metre between its side flank wall and the boundary with No.36. Also, the dwelling at No.36 sits at a higher level and is recessed back from the front of the appeal dwelling. There is a generous sized gap above the detached garage at the side of No.36, which is also recessed back from the front ofthe appeal dwelling. As a consequence, the relationship between the two dwellings is particularly spacious and the proposal would not have a terracing effect within the street scene.

Notwithstanding this, for the reasons set out in paragraph 10 above the proposed first floor side extension would unacceptably harm the character and appearance of the pair of dwellings, the street scene and the ASRC. This harm would outweigh the benefits for the appellant and their family that would result from the additional accommodation and is not something that could be satisfactorily addressed through the imposition of conditions.

I conclude on the main issue that the proposed first floor side extension would unacceptably harm the character and appearance of the pair dwellings, the street scene and the ASRC. Accordingly, it would conflict with BLP policies 6, 8 and 37, policy D3 of The London Plan and paragraph 135 of the Framework. Conversely, the proposed single storey rear extension would respect the character and appearance of the host dwelling, the pair of dwellings and the rear garden environment. It would comply with the above policies.

In view of the acceptability of the rear extension I have considered the possibility of making a split decision. As the single storey rear extension would be physically and functionally separate from the first floor side extension a split decision is possible and appropriate.

I note that the council has not suggested the imposition of any conditions. I agree that subject to a condition that requires the development to be carried out in accordance with the approved plans and documents no other conditions are necessary. This condition is necessary in the interests of certainty.

Having regard to the conclusions of the main issue and all other matters raised the appeal is dismissed in-so-far as it relates to the proposed first floor side extension. The appeal is allowed insofar as it relates to the proposed single storey rear extension with roof lantern.