Guide
Cellar tanking cost: what tanking an old brick cellar costs in the UK
Updated
Tanking a cellar is priced per square metre like any basement, but most UK cellars sit under period houses, built in brick with lime mortar and old damp, and that shapes both the method and the bill. MPS Concrete puts a single room cellar with cementitious tanking at £3,000 to £8,000.
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What a cellar costs to tank
MPS Concrete prices tanking a typical single room cellar at about £3,000 to £8,000, rising to £8,000 to £15,000 or more where the cellar becomes living space with a cavity drain membrane, sump and pump. The system itself is still £50 to £100 per m² for cementitious tanking or £80 to £150 per m² for a cavity drain membrane.
Source: MPS Concrete: Basement Tanking Cost UK
North London Damp puts cellar projects at £1,000 to £3,000 for dry storage and £8,000 to £30,000 or more for habitable space.
Source: North London Damp: Basement Waterproofing Cost Estimator
Why cellars are different
- Brick walls need old plaster, render and paint stripped back to sound masonry before a slurry will bond, so a membrane is often the safer choice on an irregular wall.
- There is rarely any outside access under a terraced house, so cellar waterproofing is almost always done from the inside.
- Narrow stairs, low ceilings and no route for materials and spoil slow the work and push up the labour per square metre.
- Salts in old brickwork may need treating, or a membrane that tolerates some residual moisture.
Those are the four cellar factors MPS Concrete sets out on its own price page.
Source: MPS Concrete: Basement Tanking Cost UK
Storage or living space
The intended use is the question that moves the price most. A cellar kept for storage can be held to a lower grade of dryness; one that becomes a bedroom, kitchen or office needs the higher grade, which in practice usually means a cavity drain membrane with a sump and pump.
Source: North London Damp: Basement Waterproofing Cost Estimator