Appeal 3308898

The appeal is dismissed.

It is considered that the main issue is the effect of the proposed development on the character and appearance of the host property and the surrounding area.

The appeal property is an already extended dwelling situated on a large plot within a primarily residential area which is also part of the [address] Conservation Area. The proposed development includes the erection of a roof extension in the form of a large rear dormer to provide a head height that would improve the level of accommodation within the roofspace for the appellant’s family.

There is a statutory duty to pay special attention to the desirability of preserving or enhancing the character or appearance of a Conservation Area which is echoed in Policy 41 of the Bromley Local Plan (BLP). [address] Conservation Area Supplementary Planning Guidance (SPG) identifies that the area comprises a late 19th century residential development, largely consisting of detached houses in an elaborate style. Many of the houses share common materials and methods of construction, including the use of red brick and slate roofs.

The SPG refers to any alterations to the structure and pitch roofs which would damage this important characteristic of the Conservation Area will normally be resisted. The SPG provides guidance that the best design solution is likely to be the insertion of small pitched roofed dormers within the rear slope.

As identified by the appellant, some of the dwellings within the Conservation Area have been altered, including the erection of roof extensions. Some details about recent alterations have been provided by the appellant but these are limited in their content. From what could be observed none of these roof extensions are of a similar design to the proposed development. Accordingly, in the absence of more detailed information and the design differences, this appeal scheme has been assessed on its own planning circumstances.

By reason of the hipped roof design, views from the road of the appeal scheme would be very limited to glimpses of the cheeks. However, the proposed extension is visible from the rear gardens of other dwellings within the Conservation Area.

The proposed extension would be of a size and bulk which would physically and visually dominate the rear roof slope of the property rather than appear a subordinate addition. The sloping sides of the proposed dormer, together with its flat roof element, would not fully respect the traditional design of the property’s hipped roof. As such, it would fail to complement the form, character and appearance of the property at roof level. There would be a conflict with BLP Policy 41 concerning development respecting or complementing the scale and form and materials of existing buildings which, for residential extensions, is echoed in BLP Policy 6 and in general the high quality design requirements for all development referred to in Policy 37.

The proposed choice of external materials and the design of the openings would not reflect the traditional roof materials and fenestration of the property and other dwellings within the Conservation Area. However, on their own these matters would not be reasons for this appeal to fail but they do add to the unacceptable harm which has been identified.

The National Planning Policy Framework refers to situations where a development proposal will lead to less than substantial harm to the significance of a designated heritage asset then this harm should be weighed against the public benefits of the proposal. In this case no specific public benefits have been identified which outweigh the identified unacceptable harm. The only benefit being associated with the improved level of accommodation for the appellant’s family.

Accordingly, it is concluded that this appeal should be dismissed because the proposed development would cause unacceptable harm to the character and appearance of the host property and the surrounding area and, as such, it conflicts with [name] 6, 37 and 41.