
Basement gyms in West London.
Chelsea · SW3 · Chelsea townhouse, opened up and fitted outCase study
Home gyms below West London houses, planned for height, sound and air.
A West London gym, built for lifting and quiet.
- One storey
- Height shared by slab, floor and ducts
- Isolated floor
- Rubber over a resilient layer
- No mezzanine
- The storey cannot be split later
NU Projects is a design and build company in Fulham SW6, founded in 2010. We handle basement gyms and spa rooms in West London W/SW, under one contract. A new basement dig typically runs £500k to £900k. Converting an existing basement runs £180k to £300k. Call 020 7731 6841, and a budget estimate typically follows within seven days.
A basement gym needs more height than most rooms. Slab, rubber flooring and ducts all come out of one storey.
Weights and treadmills make noise. So the gym floor sits on isolating pads, apart from the structure.
Fresh air and cooling run from a plant room. A steam room or sauna can share it.
Under a Chelsea townhouse, we built a gym with mirrored walls between lit pilasters. It sits in a basement under the whole house.
What the borough sets for a West London gym.
- Council
- Kensington and Chelsea governs Chelsea, Kensington and Notting Hill, through its 2024 Local Plan. Fulham sits with Hammersmith and Fulham.
- Ceiling height
- Policy CD11 gives one storey. Rubber, slab and ducts must leave room for overhead lifts.
- No second floor
- The storey cannot be split in two later. A mezzanine for a studio is not an option.
- Sound
- The gym floor sits on isolating pads, apart from the structure.
- Pool allowance
- The SPD gives a pool a little extra depth. A gym on its own gets none.
- Plant
- Gym cooling and steam share one plant room.
Source: Kensington and Chelsea’s Local Plan 2024, Policies CD4, CD5, CD11 and CD13. Read on 3 October 2026. Policies change, so we read them again for your address.
Gyms and leisure floors in West London.

Chelsea·Townhouse
Chelsea townhouse, opened up and fitted out
A basement gym with mirrored walls and a spin bike, in Chelsea.
See the project
Kensington·New build
Kensington new-build houses
A steam room on a lower leisure floor, in Kensington W8.
See the projectCase study
What a basement gym costs in West London.
£180k to £300kConverting an existing basement. A project total, from our 2026 cost guide.
£500k to £900k+Digging a new basement. A project total, from our 2026 cost guide.
A West London gym is priced as part of its basement.
The cost guide figures are whole project totals.
Fees, party wall costs, contingency and VAT sit outside them.
What West London owners ask about gyms.
In West London
- Every service in Fulham
- Basement construction in West London
- Basement swimming pools in West London
- Basement golf simulator rooms in West London
- Design and build in West London
Gyms nearby
- Basement gyms across London
- Basement gyms in Chelsea
- Basement gyms in Kensington
- Basement gyms in South Kensington
- Basement gyms in Holland Park
- Basement gyms in Notting Hill
- Basement gyms in Knightsbridge
- Basement gyms in Belgravia
- Basement gyms in Mayfair
- Basement gyms in St John’s Wood
- Basement gyms in Hampstead
- Basement gyms in Fulham
- Basement gyms in Weybridge
- Basement gyms in Cobham
- Basement gyms in Oxshott
- Basement gyms in Marylebone
- Basement gyms in Highgate
- Basement gyms in Primrose Hill
- Basement gyms in Earl’s Court
- Basement gyms in Pimlico
- Basement gyms in Westminster
- Basement gyms in South West London
- Basement gyms in North London
- Basement gyms in South London
- Fulham
- Chelsea
- Kensington
- Notting Hill and Holland Park
Further reading, from the blog
How tall should a West London basement gym be?
Enough for overhead lifts once the floor and ducts are in.
We set the floor level early to protect it.
Can I add a mezzanine to my basement gym later?
Not in Kensington and Chelsea. The storey cannot be split in two.
Will the neighbours hear the gym?
The floor sits on isolating pads, apart from the structure.
That keeps impact noise out of the party walls.
Can a basement gym have a sauna or steam room?
Yes. Cooling and steam can share one plant room.
Both are drawn into the one planning application.
See it builtNear West London
See it built.
Finished homes, designed, priced and built by NU.

Fulham · SW6 New build
Fulham, four new-build houses with basements
Four architect designed houses, each with a basement, built as a joint venture.
Case study

Fulham · SW6 Basements
Fulham basements
Basements we have dug and built under Fulham houses, close to our studio.
Case study

Fulham · SW6 House
Fulham house, refurbished throughout
A Fulham family house, renewed from the basement to the roof.
Case study
Tell us about your home in West London.
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- Already have an architect or designer? We build to their design. Working with your designer
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