Basement gyms in South London.
Chelsea · SW3 · Chelsea townhouse, opened up and fitted outCase study
A home gym below a South London house. Isolated floors, fresh air and enough height to lift.
What a South London gym has to solve.
- Isolated floor
- Weights stay off the shared wall
- Fresh air
- Mechanical ventilation, sized first
- Chelsea
- A basement gym we built
NU Projects is a design and build company in Fulham SW6, founded in 2010. We handle basement gyms and spa rooms in South London SW and SE. 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.
Many Victorian houses here hide a low cellar under the front rooms. Lowering its floor gains the height a squat rack needs.
Dropped weights carry through brick into next door. So the gym floor sits on isolating pads, apart from the structure.
A gym needs fresh air more than any other room below ground. We size the ventilation and cooling before the slab.
We built a mirrored basement gym under a Chelsea townhouse. A South London one starts from the same engineering.
What applies to a gym below ground.
- Council
- London Borough of Lambeth, under its Local Plan adopted in September 2021.
- Policy Q27
- One storey below ground, and none beneath an existing basement.
- Front lightwells
- Only where needed for daylight. In conservation areas, grilles rather than open areas are likely.
- Sound
- The gym floor sits on isolating pads, apart from the structure.
Source: Lambeth Local Plan 2021, Policy Q27 Basement development. Read on 7 October 2026. Policies change, so we read them again for your address.
What a basement gym costs in South 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 South London gym is priced from the cellar or dig beneath it.
Fees, party wall costs, contingency and VAT sit outside them.
What South London owners ask about gyms.
In South London
- Every service in Battersea and Clapham
- Basement construction in South London
- Basement swimming pools in South London
- Basement golf simulator rooms in South London
- Design and build in South 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 West London
- Basement gyms in South West London
- Basement gyms in North London
- Battersea and Clapham
- Wandsworth, Putney and Barnes
- Dulwich
- Wimbledon
Further reading, from the blog
Can a South London cellar become a gym?
Often, once the floor is lowered for height.
We survey the footings to see how far it can go.
Will neighbours hear a basement gym?
Not if the floor is isolated from the structure.
We stand it on pads, apart from the shared walls.
Does a basement gym need a lightwell?
Not always. Lambeth allows one only where daylight needs it.
Good ventilation matters more for a gym.
What does a basement gym cost in South London?
Converting an existing basement is £180k to £300k.
A new dig is £500k to £900k and more, as project totals.
See it builtNear South London
See it built.
Finished homes, designed, priced and built by NU.
Kensington · W8 New build
Kensington new-build houses
Two new-build houses with triple basements, built under one contract.
Case study
Chelsea · SW3 Townhouse
Chelsea basement and extension
A new basement, a kitchen extension and a full interior renovation.
Case study
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
Tell us about your home in South London.
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- Already have an architect or designer? We build to their design. Working with your designer
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