Kensington Victorian Terrace — Conservation Area Rear Extension

The clients owned a Victorian terraced house in a Kensington conservation area, managed by the Royal Borough of Kensington and Chelsea (RBKC) — one of the most design-conscious planning authorities in England. The brief was to extend the ground floor to the rear to create an open-plan kitchen-dining room, adding approximately 18m² of floor space and improving the connection to the garden.

The house was entirely within the conservation area, with the rear garden not visible from the street. The property had an existing rear addition of limited quality (a later addition, not original to the house) that was to be demolished as part of the works.

RBKC's planning officers are experienced and demanding. The design approach was to use high-quality materials in a clearly contemporary idiom — neither pastiche nor wilfully contrasting. A lantern roof light over the main dining area brought natural light into the centre of the deep extension plan, avoiding the dark-at-the-back problem common in deep rear extensions.

The rear elevation was finished in stock brick to match the existing rear wall, with large fixed and opening glazed sections in slim steel sections — a material considered appropriate by RBKC conservation officers in this conservation area context.

Pre-application advice was sought from RBKC before the formal application was submitted. The conservation officer's feedback focused on the lantern height (lowered by 300mm from the initial design) and the specification of the brick (a specific handmade stock brick was agreed). These changes were incorporated before the application was submitted.

The formal application was submitted to RBKC following the pre-application process. The application included: planning drawings (location plan, block plan, existing and proposed floor plans, existing and proposed elevations, sections, and roof plan); a Design and Access Statement addressing the conservation area character and the design rationale; and a materials schedule confirming the agreed brick and glazing specifications.

The application was granted consent under delegated powers in eight weeks from registration. The only condition beyond standard ones was a pre-commencement material submission, which was discharged promptly using the agreed materials schedule.

The building regulation package covered the new extension structure, insulation to Part L, the lantern rooflight specification, the new bifold glazed doors, drainage from the extension roof, and the connection to the existing house drainage. A structural engineer provided calculations for the steel beam at the rear wall opening and the new extension roof structure.

Construction was completed in fourteen weeks. The finished extension added 18m² of high-quality open-plan kitchen-dining space connected directly to the garden.