Mansard roof and extensions at House excluding basement flat, South Kensington, London SW3

What was proposed

The application proposed a mansard roof, extensions to the rear closet wing and infill, and internal and external alterations.

“The heritage significance of the listed building includes its architectural design and elevational hierarchy, its contribution to the setting of the listed terrace and the internal planform. 4.The proposal and any relevant planning history 4.1Planning permission and listed building consent is sought for the following: ·The construction of a mansard roof extension at third floor level; ·An additional storey extension to the rear closet wing to extend it to second floor level;…”

Officer report

The site

The property is a Grade II listed townhouse within the Chelsea Conservation Area, forming part of a wider terrace.

“/PP/26/00411:2 · Three or more objections were received during the consultation period and the recommendation is to grant. 3.The site and its surroundings 3.141 Sydney Street originally dates from the early 19th century. The building is Grade II listed and is in the Chelsea Conservation Area. The property forms part of a wider terrace, creating a uniform composition.”

Officer report

Earlier applications

A related application for alterations to the basement flat, including a smaller infill extension, was under determination.

“4.3The relevant planning history is set out below: ReferenceDescriptionDecision LB/26/00394 PP/26/00395 Internal and external alterations including replacement of existing metal stair to front lightwell with new black painted metal stair, enclosure of open space beneath ground floor entrance stairs with new partition wall and door to form lobby entrance to Basement Flat, replacement of existing 1969 infill extension beside rear closet wing with smaller infill extension; and…”

Officer report

Consultation responses

The Conservation and Design consultee raised no objections subject to conditions, while nearby objections were assessed and answered.

“/PP/26/00411:5 7. If permitted and built, the proposal would not require a payment towards funding additional infrastructure under the Borough’s Community Infrastructure Levy or a payment towards funding Crossrail under the Mayor of London’s Community Infrastructure Levy. 8.Consultations carried out Comments from interested parties 8.1The application was advertised in the Gazette on 27/03/2026.”

“In the case of the infill extension, a smaller extension is proposed than the existing. The construction of a mansard roof extension would help unite the terrace as a whole. Other consultees and organisations ConsulteeComment Where in the report this is considered Conservation and Design No objections subject to conditions.Paras. 6.2 – 6.6”

Officer report

Who spoke

There were no speakers for this item.

The committee’s decision

The committee granted planning permission by majority with the conditions listed in the officer report.

“Resolved by majority (Cllr Taylor-Smith recused himself for these items): Planning permission be granted with the conditions listed in Section 9 of the report for S038 and listed building consent be granted with the conditions listed in Section 2 of the report for S039.”

Minutes