Basement gyms in North London.

Chelsea · SW3 · Chelsea townhouse, opened up and fitted outCase study

Strength, cardio and recovery under one North London roof. Planned around the ground first, then the kit.

Strength and recovery beneath the hills.

Policy A5: A single storey sets the ceiling
Audited: Ground report checked independently
Spa option: Steam or shower beside the gym

NU Projects is a design and build company in Fulham SW6, founded in 2010. We handle basement gyms and spa rooms in North London NW and N. 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 North London houses stand in long, sloping gardens. That slope can give a lower floor daylight at the back. A gym facing the garden feels far less like a cellar.

Hill ground carries springs and clay, so the slab is engineered with care. Heavy plates and treadmills sit on a cushioned, separated deck. Racks bolt to an inner lining, clear of shared structure.

Training rooms run warm, so cooling and fresh air are designed from the start. Steam rooms and showers need their own drainage and extract. We plan them with the gym, not after it.

Camden caps basements at one storey, under half of each garden.

What Camden asks of a gym below ground.

Council: London Borough of Camden, under its Local Plan adopted in July 2017.
One storey: Policy A5. One storey only, and never under an existing basement.
The garden: No more than half of each garden. Less than 1.5 times the house’s footprint.
Impact: A Basement Impact Assessment, independently audited. Neighbour damage is capped at Burland category 1.
Guidance: Camden’s Basements planning guidance, adopted January 2021, explains how each test is applied.

Source: Camden Local Plan 2017, Camden’s Basements guidance 2021, and the Hampstead plan 2025. Read on 5 October 2026. Policies change, so we read them again for your address.