Building work in Knightsbridge: area guide

This is our area guide to building work in Knightsbridge (SW7, SW1, SW3, Kensington and Chelsea and Westminster): the housing, the council rules that apply (the Royal Borough of Kensington and Chelsea or Westminster City Council for planning) and every service we offer here. For whole-house refurbishment go to Home renovation in Knightsbridge.

Most homes in Knightsbridge are flats, and mansion block flats behave nothing like houses once building work starts. There is no permitted development, the lease governs what may be altered, the freeholder's surveyor reviews the drawings, and the block itself sets the hours, the lift access and the delivery route. We work within those constraints across the streets around Brompton Road and the Brompton Oratory, from apartments close to Harrods to blocks facing Hyde Park. The building work in a flat is often the straightforward part. The coordination around it, which differs by service, decides whether a job runs cleanly or stalls.

The Council Tax list puts Knightsbridge at about 10,560 homes, 83% flats against 17% houses; 66% went up before 1919, 19% between the wars and 15% after 1945. VOA Council Tax stock of properties, March 2025, for Hans Town and Brompton. Counts rounded by the VOA.

What can and cannot move in a mansion block sets the job

Mansion blocks are built around solid masonry cross walls that carry several storeys, with lighter partitions filling in between them. From inside a single flat the two look identical once plastered, so the first task is establishing which is which by opening up, not by tapping and guessing: a partition is an open-plan conversion job, a cross wall is not. Chimney breasts inside a flat are another trap, because the stack continues through the flats overhead and cannot simply lose its base, so a chimney breast removal needs both an engineer's design and the freeholder's consent.

Opening a cross wall is load-bearing wall removal: the beam is sized by a structural engineer we appoint and we build exactly to the drawing issued, never to our own calculation. Bearings go into the masonry on padstones that spread the load, and temporary support carries the floors above while the opening is cut. Because these walls are usually shared with a neighbouring flat, party wall notices apply, and the notice periods sit in the programme from the beginning rather than surfacing when the steel is already on order.

Bathrooms and kitchens above other homes follow the risers

Every wet room in a block sits above somebody else's ceiling, which raises the standard for the waterproofing underneath it. A tanking system taken up the walls and lapped into the tray, correctly formed falls to the outlet, and pipework tested before anything is tiled are the difference between a wet room that lasts and a claim against your insurance. Acoustic separation matters just as much, because a hard floor and an unisolated waste pipe will be heard clearly below. Both fall under building regulations and are inspected, not left to preference.

Layout in a flat is dictated by the existing risers. Soil and waste connections are fixed points, so a bathroom renovation or kitchen renovation can move a room only as far as the gradients allow, and extract ventilation needs a route to outside air that the block will accept. Licence to alter conditions often require reinstatement at the end of the lease, restrict noisy work to set hours and require protection to lifts and common parts. We keep one person as site contact and arrange the building control inspections for the notifiable elements.

Where to go next for work in Knightsbridge: kitchen renovation in Knightsbridge, house extensions in Knightsbridge, the Kensington and Chelsea area guide, building work in South Kensington, building work in Kensington and How Long a Renovation Takes.