Appeal 3268986

The appeal is allowed and planning permission is granted for erection of double-pitched mansard roof extension and extension of parapet wall at [site address] in accordance with the terms of the application, [name]/20/06395, dated 18 November 2020, 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: 2020-012-LP – location plan 2020-012-02 – existing floor plans 2020-012-03 – existing elevations 1 2020-012-04 – existing elevations 2 2020-012-05 – existing section 2020-012-06 – proposed floor plans 2020-012-07 – proposed elevations 1 2020-012-08 – proposed elevations 2 2020-012-09 – proposed section 2020-012-10 – detailed elevation 2020-012-11 – detailed section

The external surfaces of the development hereby permitted shall be constructed in the materials shown on plans no. 2020-012-08 and 2020-012-10.

The external doors hereby permitted shall be timber framed and painted, and so maintained thereafter.

The railings to the Juliette balcony hereby permitted shall be painted black, and so maintained thereafter.

Prior to the commencement of development, a Site Construction Management Plan (SCMP) shall be submitted to, and approved in writing by, the Council’s Construction Management Team. A copy of the approved SCMP shall then be submitted to the Local Planning Authority to be placed on the property record. The development shall be carried out in accordance with the approved SCMP.

Since the Council made its decision, the London Plan has been adopted. The main parties were invited to comment on any matters arising from this change in policy context which may be relevant to this appeal, but no issues were raised.

There has been a further change in that a revised version of the National Planning Policy Framework has been published, but the section relating to the conservation and enhancement of the historic environment, which is particularly relevant to this appeal, remains largely unaltered. I am satisfied that the changes to national planning policy do not prejudice the cases made by either party.

The main issue is whether the proposal would preserve or enhance the character or appearance of the Hans Town Conservation Area and the setting of the adjacent listed building, [address].

The appeal site is located within the northern part of the Hans Town Conservation Area (CA), which is characterised by large buildings associated with the internationally famous shopping area, interspersed with elegant residential areas formed of substantial mansion blocks.

The dense, urban form of the area, with large blocks of development fronting directly onto the streets, means that where green spaces and gaps between the buildings exist, they provide relief from built form. The Conservation Area Appraisal notes that even small gaps between buildings, including those at higher level between taller buildings, provide visual breathing space, and are important to the character of the CA.

Such a gap is provided by [site address] (No. 44), a two storey town house fronting onto the short section of [address] between [address] and [address]. The modest sized dwelling, with white stucco finish, sits between, and slightly forward of, two much larger buildings which, whilst very different in appearance, are nonetheless typical of the range of building styles found within the CA, and contribute positively to it.

Number [address] (No. 18) is the end property of an elegant [name] listed terrace. This substantial building is grand and formal in appearance, and faces onto a matching stucco terrace on the other side of [address]. The flank elevation of No. [address], where it reduces in height from four storeys to three, with the lower element of the building, numbered [address], adjoining the appeal property. The stepping down in levels of the flat roofed buildings, from the full height of the listed terrace, to the two storey appeal property, forms a distinctive element within the streetscene.

To the other side of the appeal property is [address], which forms part of a large and elaborate red brick Edwardian terrace. The diminutive scale of the appeal property allows clear views of the steeply sloping front gable and the tall, ornate chimney stacks of the Edwardian building, which add to the appreciation of its considerable height along the [address] elevation.

The proposed mansard roof extension would increase the height of No. 44, most noticeably through the raising of the parapet by some 450mm, but the appeal property would remain appreciably lower than the adjoining [address]. The mansard extension would slope away from the front elevation and the change in the pitch of the roof would reduce the impression of the increased height of the building.

The dark coloured slate shingle finish, and lack of windows, would further limit the visual impact of the proposal within the streetscene, so that it would appear as a recessive element of the building which would not compete with the buildings on either side. The proposed raised parapet would match the materials of the host building, and would be consistent with its existing proportions and formal character.

When viewed from the street, the stepping down from 42 to [site address] would be slightly less pronounced as a result of the proposed development, but it would still be clearly apparent, and the dominance of [address] over the subservient rear elements along the [address] frontage would be retained. The full extent of the steeply pitched roof of the adjacent Edwardian building would remain visible, and the high level gap between the tall buildings on either side of the appeal property, which forms an important element within the streetscene, would be maintained.

Although the proposed development would be visible within the streetscene, it would not cause harm to the character of the host property, or to its relationship with the adjacent buildings. The effect on the character and appearance of the CA, and the setting of the listed terrace, would be neutral.

I conclude that the proposal would preserve the character or appearance of the Hans Town Conservation Area and the setting of the adjacent listed building, [address]. The proposal complies with Policies CL1 and CL2 of the Kensington and Chelsea Local Plan 2019, which require development to respect the existing context, character and appearance, and to be of the highest architectural and urban design quality. The proposal is consistent with Policies CL3 and CL4 of the same plan, concerning the protection of heritage assets. It also complies with Policy CL8, which requires additional storeys to be architecturally sympathetic to the age and character of the building, and with Policy CL11, concerning the protection of views.

I note the Council’s reference to guidance in the Hans Town CA Proposals Statement regarding the principle of additional storeys in this location, but no such stipulation is included in the version of the Conservation Area Appraisal that I have been provided with. In any event, I have concluded that the proposal complies with the development plan, and as such is acceptable.

Neighbouring occupiers have expressed concerns over the effect of the proposal in terms of potential loss of light, privacy and increased sense of enclosure. However, the relative orientation of the proposed mansard in relation to nearby windows and amenity areas would be such that the proposal would not result in unacceptable loss of light, nor would it appear overbearing. The proposed mansard would introduce a new window at roof level, but given the existing mutual overlooking in the area, I am satisfied that it would not result in undue loss of privacy to neighbouring occupiers.

In addition to those dealing with implementation, materials and plans conditions, the Council has suggested conditions requiring that the external doors be timber framed and painted, and that the railings be painted black. A pre-commencement condition has also been suggested which would require the submission, approval and adherence to a Construction Management Plan. I agree that these conditions are necessary to safeguard the character of the area and the living conditions of neighbouring occupiers, and have imposed them with minor wording changes, in the interests of precision.

For the reasons set out, the appeal is allowed subject to the conditions.