
Loft conversions in Knightsbridge.
Knightsbridge · SW1 · Knightsbridge townhouse, whole house refurbishmentCompleted work, photograph
Knightsbridge roofs answer to two councils. We find out which one before anything else.
A Knightsbridge roof, and the boundary under it.
- Two boroughs
- Westminster east, Kensington and Chelsea west
- 2018
- Knightsbridge Neighbourhood Plan made
- Three homes
- Built here by our own team
NU Projects is a design and build company in Fulham SW6, founded in 2010. We handle loft conversions, dormers and mansards in Knightsbridge SW1X, under one contract. A main dormer loft typically runs £90k to £140k. A mansard loft runs £140k to £220k. Call 020 7731 6841, and a budget estimate typically follows within seven days.
Knightsbridge straddles a borough line. The east falls to Westminster, the west and south to Kensington and Chelsea.
Both refuse extra floors on unaltered terraces. Each phrases it in its own guidance.
Most homes here are leasehold apartments in stucco terraces or mansion blocks. A managing agent usually stands between you and the roof.
The handful of townhouses near the park are the realistic loft candidates.
We have refurbished two townhouses and an apartment here, so we know these buildings.
What each council allows on a Knightsbridge roof.
- Council
- Westminster or Kensington and Chelsea, depending on the address. We confirm which.
- Westminster side
- Roof extensions are refused on complete terraces with largely unaltered roof lines.
- Kensington and Chelsea side
- Policy CD12 resists an extra storey wherever a group roofline is intact.
- Neighbourhood plan
- Westminster’s side has the Knightsbridge Neighbourhood Plan, made in December 2018.
- The lease
- Most homes are leasehold. A freeholder’s licence sits beside any council consent.
- Listed buildings
- Many are listed. Consent can reach the roof structure and top rooms.
Source: Westminster’s Roofs guide to alterations and extensions on domestic buildings. Read on 6 October 2026. Policies change, so we read them again for your address.
Our Knightsbridge townhouses.

Knightsbridge·Townhouse
Knightsbridge townhouse, whole house refurbishment
A Knightsbridge townhouse we refurbished throughout, stair to top floor.
See the project
Knightsbridge·Townhouse
Knightsbridge townhouse, pool and wine room
Another Knightsbridge townhouse, with a pool and wine room we built.
See the projectCompleted work, photographs
What a loft conversion costs in Knightsbridge.
£140k to £220kA mansard loft. A project total, from our 2026 cost guide.
A loft here is priced once both council and freeholder are known.
The guide figure is a project total.
Fees, party wall costs, contingency and VAT sit outside it.
What Knightsbridge owners ask about lofts.
In Knightsbridge
- Every service in Knightsbridge
- House extensions in Knightsbridge
- Architectural design in Knightsbridge
- Planning consultants in Knightsbridge
- Party wall surveying in Knightsbridge
Lofts nearby
- Loft conversion across London
- Loft conversion in St John’s Wood
- Loft conversion in Highgate
- Loft conversion in Fulham
- Loft conversion in Marylebone
- Loft conversion in Notting Hill
- Loft conversion in Chelsea
- Loft conversion in Kensington
- Loft conversion in South Kensington
- Loft conversion in Belgravia
- Loft conversion in Mayfair
- Loft conversion in Holland Park
- Loft conversion in Hampstead
- Loft conversion in Primrose Hill
- Loft conversion in Earl’s Court
- Loft conversion in Pimlico
- Loft conversion in Westminster
- Loft conversion in Weybridge
- Loft conversion in Cobham
- Loft conversion in Oxshott
- Belgravia
- South Kensington
- Chelsea
- Mayfair
Further reading, from the blog
Which council decides a Knightsbridge loft conversion?
It depends which side of the borough line the house stands.
East is Westminster. West and south are Kensington and Chelsea.
We check the address before any drawing.
Can a Knightsbridge apartment owner build into the roof?
Only with the freeholder’s licence and planning permission.
Flats carry no permitted development rights for roof work.
The managing agent is usually the first call.
Does the Knightsbridge Neighbourhood Plan cover my roof?
Only on the Westminster side, where it was made in 2018.
It sits beside Westminster’s own roof guidance.
Is a mansard realistic on a Knightsbridge townhouse?
Where neighbours already have one, sometimes.
On an untouched terrace, both councils normally refuse.
Listed townhouses add a further consent.
Tell us about your home in Knightsbridge.
Your name and one way to reply are enough. It goes straight to the studio.
- Already have an architect or designer? We build to their design. Working with your designer
- An NDA on request, and your home is never published without your consent. How we work in confidence