Appeal 3338128

The appeal is dismissed.

I have taken the description of development from the planning application form. Although it is different to that on the decision notice, no confirmation has been provided that the change to the wording of the description was agreed by both main parties.

The main issues are: • whether the proposal would preserve or enhance the character or appearance of the [address] Conservation Area, having particular regard to the significance of the host building as a non-designated heritage asset; and, • the effect of the proposed single storey rear extension on the living conditions of the occupants of [address] with regards to outlook.

As the appeal site is within the [address] Conservation Area (the CA), I have had regard to Section 72(1) of the Town and Country Planning (Listed Buildings and Conservation Areas) Act 1990 which requires that special attention be paid to the desirability of preserving or enhancing the character or appearance of that area.

The Supplementary Planning Guidance for [address] Conservation Area (the SPG) identifies that the area predominately consists of detached and semi-detached houses that were built in the 19th century and exhibit a similar character. The significance of the CA primarily derives from the mostly intact formal rows of houses that reflect the Victorian suburban form and are important components that contribute to the significance of the CA as a whole.

The host building is a semi-detached house. It is one of twelve properties that are locally listed and are a non-designated heritage asset. The properties are an attractive group of late Victorian houses in [name] style. The significance of these properties is derived from the preservation of the original and traditional appearance with distinctive architectural quality and detailing that is reflected across the properties and positively contributes to the character and appearance of the CA as a whole.

Although the rear elevation of the house has been altered, it retains much of its characteristic features which include the prominent three storey projection with gable roof and the bold sill and header detailing around the windows. The rear elevation displays a hierarchy of window proportions whereby typically window size decreases moving up the building with the top floor window in the rear projection being of a smaller size than the window below.

The adjoining house generally mirrors the design of the appeal house with the rear projection, simple roof form and hierarchy of windows reflected. These elements of design continuity produce a pleasing sense of symmetry between the house and its neighbour. The Local List designation description also references the mirror image design of the houses.

The proposed dormer window would infill most of the roof plane between the roof of the rear projection and the chimney and would obscure the existing rear roof slope. Due to a combination of its height, width and scale, the dormer window would have a bulky appearance and would dominate the rear elevation and roof slope of the house, which would be a stark contrast with the historic simple form and proportions of the existing roof. It would also have a Juliette balcony window opening and its length would disrupt the hierarchy of the architectural order of the windows of the house.

The dormer window would draw the eye to this part of the roof plane and would visually compete with the gable roof of the rear projection, detracting from its status as a key architectural feature. It would also unbalance the appearance of the house eroding the existing sense of symmetry between the house and its neighbour. Whilst the dormer window would not be visible from public views, this harmful effect on the appearance of the house would be visible from the windows and rear gardens of the surrounding properties.

My attention has been drawn to the dormer window present at a neighbouring property. This dormer window appears to be set further up the roof slope with a greater setback from the eaves and is smaller in size with two windows. It is of a different design and is not directly comparable to the proposed dormer window. Notwithstanding this, each proposal must be judged on its individual merits. This example does therefore not weigh in support of the proposed dormer window.

The existing conservatory is of little design merit and does not reflect the architectural style of the house. The proposed single storey rear extension would be built in facing brickwork and the window proportions would reflect the hierarchical approach to fenestration including the header detailing around the windows. It would therefore correspond with the design of the house and would be appropriately integrated. Whilst the extension would wraparound the rear projection, it would sit below the window sill of the first floor windows and would be visually subservient. This would ensure that the rear projection remains the defining feature of the house.

The single storey rear extension would be larger in scale and footprint than the existing extension but it would not be seen to be disproportionate when viewed against the house as a whole, particularly as the house is of a substantial size. I accept that the single storey rear extension at [address] was not approved under the current local plan, however, it does form part of the character of the CA. Based on the evidence before me, the single storey rear extension would be similar to that built at this neighbouring property. It would therefore not be an uncharacteristic addition.

The proposed rooflights would be small in size and would occupy a very limited proportion of the front and side roof planes. Although they would be a modern addition, they would not disrupt the appearance of the roof to an unacceptable degree.

[name] have found the proposed single storey rear extension and rooflights to be acceptable, the proposed dormer window would cause harm to the house's distinctive appearance. This would diminish the positive contribution that the house makes to the CA causing harm to the character and appearance of the CA.

Although localised in its effect, the harm caused to the CA would be less than substantial. Nevertheless, this attracts considerable weight and importance. In accordance with paragraph 208 of the National Planning Policy Framework, where a development would lead to less than substantial harm to the significance of a designated heritage asset, this harm should be weighed against the public benefits of the proposal.

The existing conservatory would be removed and the brickwork on the front elevation would be restored. These would be visual benefits improving the character and appearance of the house. However, these benefits are afforded limited weight given that these works could be carried out separately from the proposal. There would be some economic benefits through the construction phase. However, owing to the scale of the proposal, such benefits are only likely to be of a small scale. The public benefits of the proposal are therefore of limited weight and are insufficient to outweigh the less than substantial harm.

For these reasons, I conclude that the proposal would fail to preserve or enhance the character or appearance of the CA and would cause harm to the significance of the house as a non-designated heritage asset. The proposal therefore conflicts with Policies 6, 37, 39 and 41 of the Bromley Local Plan 2019 (the Local Plan) and Policy HC1 of the London Plan 2021. These policies amongst other things, require development to be sympathetic to the appearance of locally listed buildings and preserve and enhance the characteristics and appearance of conservation areas.

The proposal would also conflict with the guidance in the SPG which aims to secure the preservation or enhancement of the character and appearance of the area.

The proposed single storey rear extension would be built close to the shared boundary with [address] (No.13). Because of its depth, the extension would project beyond the rear elevation of No. 13. When combined with the proposed height, the occupants of No. 13 would be faced with a blank elevation. Even if No. 13 sits at a higher ground level, because of the size of the extension it would be visible above the existing boundary fence and would be in sufficiently close proximity to result in undue harm to the outlook from the nearest rear-facing window, as well as from the garden space of No. 13.

[name] accept that the extension is similar to the rear extension approved at [address], in the absence of further details, I cannot be reasonably certain that the extension at this property is directly comparable with the appeal proposal in terms of its impact on outlook. My assessment is based on the proposal before me and the relationship with the neighbouring property.

I therefore conclude that the proposed single storey rear extension would cause adverse harm to the living conditions of the occupants of No. 13 with regards to outlook. This conflicts with Policies 6 and 37 of the Local Plan, which amongst other things, require the design and layout of extensions to respect the amenity of occupiers of neighbouring buildings.

The appellant raises concerns regarding how the Council handled the planning application, however, this would not alter my conclusions on the planning merits of the proposal.

The proposal conflicts with the development plan and the material considerations do not indicate that the appeal should be decided other than in accordance with it. Therefore, the appeal is dismissed.