Appeal 3314465

The appeal is allowed and planning permission is granted for a double storey side extension with an open porch to protect the main entrance door on the front elevation, first floor rear extension and loft conversion with the erection of an L shaped box dormer, and demolition of an existing garden shed at [site address] , Kent, [postcode] in accordance with the terms of the application, [name]/223/01993/FULL6, dated 17 May 2022, and the plans submitted with it, subject to the following conditions:

The development hereby permitted shall begin not later than 3years from the date of this decision.

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.

The development hereby permitted shall be carried out in accordance with the following approved plans, drawings: BL/DRG/270921/01, 02, 03, and 04.

I consider the main issue to be the effect of the proposed development on the architectural integrity of the host property and thereby the wider street scene.

The appeal property, [site address] is a detached two-storey, inter war house located on the corner of [address] and Forest Way.

The area comprises a mix of large detached two-storey dwellings and smaller semi-detached dwellings of varying architectural styles. Nevertheless, as with number 96 hipped roofs and expressed timber framing are common features of many of the properties. [name] observed a number of the surrounding properties have been the subject of alteration and extension and there are also examples of mansard or crown style roofs, including the neighbouring property, [address].

The appellant proposes a two-storey side extension with entrance porch canopy, two storey rear extension, loft conversion with an ‘L’ shaped box dormer and roof lights to the front and side roof slopes.

The Council raised no objection to the two-storey rear extension, porch canopy and found the choice of external materials acceptable. From what I have seen and read I would concur with its findings on these matters.

As identified above the property is located on a prominent corner plot and therefore any design solution for an extension to the host property should have due regard to the visual transition from one street façade/scene to the next. Furthermore, in this context the three-dimensional form, massing and detail proposed while respecting the design of the neighbouring properties does not, in my judgement, need to slavishly follow that of those which only face the street.

The proposed design, while maintaining a hipped roof form to the front elevation has introduced gables to the rear and side elevations. This would be a departure from the established roof form. However, when viewed from [address] the contrasting gable ended roof of the extension would clearly define this house as the end of this section of development in the road. In this context therefore, I consider that the introduction of a gable end facing Forest Way in contrast to the hipped roof of the street façade would be acceptable. In addition, I consider that the proposal to extend the dwelling closer to Forest Way while helping to address the corner does not result here in creating an unduly excessive addition to the host property.

The ‘L’ shaped box dormer is large. However, it would be set down below the ridge line of the host property, located above the eaves line of the main roof and be set well in from the roof verges. On balance therefore I consider that although large it would not, in this case visually overwhelm the roof.

The mansard style roof here would allow, while maintaining the roof pitch of the host property, the new roof to finish below the ridge line of the main house. Thereby, despite its overall size it would be visually subservient to the existing dwelling.

Furthermore, the proposed development would alter the form and massing of the original dwelling. However, the design, while retaining the hipped roof to the front elevation would also replicate many of design details found in the host property, roof pitch, expressed timber framing, fenestration proportions, matching materials etc.

For all these reasons I conclude in respect of the main issue that, while the proposed extension would be relatively large in the context of the host property, due to the overall design and its corner plot location it would nevertheless appear as well-mannered development in this location, one that would not unduly impact on the architectural integrity of the host property or the wider street scene. It would therefore accord with the objectives of Policies 6 and 37 of the London Borough of Bromley Local Development Framework– Local Plan ([name] 2019) as they seek to secure, along with other things, high-quality imaginative and attractive design that is compatible with surrounding development.

The conditions follow from those suggested by the Council. To ensure a high quality development, I shall include a condition about the materials to be used in the construction of the external surfaces of the building.

In the interests of certainty, I shall also impose a condition requiring the development to be undertaken in accordance with the approved plans.

For the reasons given above and having regard to all other matters raised, I conclude that the appeal should be allowed.