Basement contractors in London. We design, engineer and build basements under one contract. Basement cost in London, the 2026 figures.
Basement conversions in Fulham, Chelsea and Kensington.
Most London bunkers are not separate structures.
They are one room in a basement, designed in from the start.
From the hallway, it looks like any other room.
This is how they are planned, and how long each route takes.
Three routes to a protected room
A protected room inside your existing basement is the quickest basement route.
Design and approvals take 2 to 3 months. The build takes 3 to 5 months.
It is usually smaller, built as a room inside the room.
A new basement with a bunker is the fullest option.
Planning, design and permissions take 6 to 9 months. The build takes 12 to 18 months.
That is about two years from first drawing to finished room.
Without a basement, a safe room in the house is the third route.
Design takes 4 to 6 weeks, and the build 8 to 12 weeks.
These are typical timescales. Every house is different.
Why it has to be designed in early
The concrete, the door and the air routes go in with the structure.
Added later, they cost more and do less.
So raise it before the engineer designs the basement.
Many protected rooms double as a cinema, a gym or a wine room.
What changes in the build
The walls, floor and roof are thicker reinforced concrete.
A steel shelter door is cast into the wall, with a rubber seal.
Every service entry through the concrete is sealed.
Filtered air comes in under slight pressure.
A second way out leads to the garden.
Batteries sit outside the room, for fire safety.
Planning and the honest limits
It is approved as a basement room, not as a shelter.
Most central London boroughs allow one storey below ground.
Air intakes, hatches and plant are what planners look at most.
No home room can promise survival near a detonation or in a mass fire.
It can cut exposure to fallout and to blast at a distance. It buys you time.
Kept private
We keep the location and the details private.
An NDA is available on request.
Drawings are shared only with the people who need them.
Read more in why London homes are adding panic rooms.
Thinking about a protected room in a London home?Fill out the contact form or call 020 7731 6841. Every conversation is private.
This is the work we do. Basement contractors in London, or ask for a cost estimate.
Published 14 November 2026. Written by the NU Projects studio, edited since for house style and accuracy.
