Cavity drain membranes, tanking and drainage systems that turn damp cellars into dry, usable rooms, designed by Basement Waterproofing Association members. Covering Kensington & Chelsea, Richmond & Barnes and Greenwich & Lewisham and across London.
Book a surveyBelow-ground rooms in London sit against wet ground, so water is pushed into them under pressure through walls, floors and the joints between them. A standard damp proof course can't deal with that.
Whether you want a dry storage cellar or a full conversion into living space, we design and install the right waterproofing system for your building and how you plan to use the room.
London has more basements, cellars, vaults and lower ground floors than anywhere else we work, and converting them is one of the best ways to add space to a London home.
With London Clay and high water tables in many boroughs, the waterproofing has to be right. Our projects range from basement damp proofing in Marylebone and Knightsbridge to structural waterproofing for the Burberry flagship on Regent Street.
Much of London sits on London Clay, which holds water and swells and shrinks with the seasons, while areas close to the Thames and its lost tributaries have high water tables. That combination puts constant moisture pressure on lower ground floors, vaults and basements, and is why so many London basement projects need a properly designed waterproofing system.
London's housing stock is dominated by Victorian and Edwardian terraces, Georgian townhouses and mansion blocks, many now split into flats. Most were built with solid brick walls and original slate or bitumen damp proof courses that are now well over a century old. Raised pavements and garden levels, lower ground floors and shared party walls all make damp more likely, and conversions often introduce new kitchens and bathrooms without enough ventilation.
Stucco-fronted townhouses and mansion blocks with lower ground floors and vaults under the pavement, where basement waterproofing and damp to front lightwells are everyday problems.
Riverside villas and cottages close to the Thames, where high groundwater, tidal flooding and damp cellars go hand in hand.
Georgian and Victorian houses on sloping ground near the river, where earth banked against rear walls and old suspended timber floors lead to damp and rot.
For most conversions we recommend a cavity drain membrane (CDM) system. A studded membrane is fixed to the walls and floor, leaving a small air gap that lets any water that gets through the structure drain freely into a perimeter channel and away, usually to a sump pump. Because it manages water rather than trying to hold it back, it copes well with older walls and high water tables.
Where conditions suit, cementitious tanking can be applied directly to sound masonry to create a continuous waterproof barrier. We often combine approaches, for example tanking to light wells and a membrane system in the main room.
We can provide the waterproofing on its own, ready for your builder, or manage the specialist work from survey through to a dry, finished shell. Every system is designed in line with recognised industry standards and comes with a written guarantee.
A PCA-qualified, commission-free surveyor visits your London property, investigates with calibrated equipment and identifies the cause.
You receive a clear written report explaining what we found and what we recommend, with a fixed quotation and no hidden extras.
Our own trained team carries out the work, protecting your home, keeping dust down and leaving everything clean.
You receive a written guarantee, which can be protected by an Insurance Backed Guarantee for a single premium.
Our surveyors are in London every day, travelling in from our Thames Ditton office in south-west London. We regularly work in Bromley, Acton, Balham, Battersea, Biggin Hill and Blackheath, and throughout Westminster, Kensington & Chelsea, Hammersmith & Fulham, Wandsworth, Lambeth and Southwark.
Towns and areas we cover in London
One recent example of our basement & cellar waterproofing work in London: Structural waterproofing, Burberry, 121 Regent Street.
Find out more about our basement & cellar waterproofing service.
Book a survey
If you’ve noticed any of these issues, arranging a professional survey is the best way to identify the cause and prevent further damage.
Most can. Headroom, access, natural light and the water table all affect what is possible and what the waterproofing needs to do. A survey tells you what is realistic before you commit to plans.
A studded plastic membrane fixed to the walls and floor that creates a drainage gap. Water that gets through the structure runs behind the membrane into a channel and is pumped or drained away, so the room stays dry.
If water can't drain away naturally, yes. Your surveyor will advise. Where a pump is fitted we recommend a backup and regular servicing.
Yes. Our systems carry a written guarantee, which can be protected by an Insurance Backed Guarantee (IBG) for a single premium. We are members of the Basement Waterproofing Association.
Yes. Much of our London work is in flats, maisonettes and lower ground floor conversions. We can liaise with managing agents and freeholders where the cause of a problem sits in a communal part of the building or a neighbouring flat.
Yes. Our teams work in central London every week and plan for parking suspensions, congestion charge zones and restricted access, so you don't have to.
Our surveyors are in London every day, travelling in from our Thames Ditton office in south-west London. Towns we visit regularly include Bromley, Acton, Balham, Battersea, Biggin Hill, Blackheath, East Ham and Hammersmith. If yours isn't listed, give us a call and we'll confirm.
Also in London
Our other specialist services for London homes, landlords and businesses.
Rising damp, penetrating damp and damp proof courses. Most common around Kensington & Chelsea and Richmond & Barnes.
Dry rot, wet rot and woodworm. Most common around Greenwich & Lewisham and Kensington & Chelsea.
Black mould, streaming windows and ventilation. Most common around Hackney and Kensington & Chelsea.
Pre-purchase and mortgage surveys. Especially worthwhile for older homes around Kensington & Chelsea and Islington & Camden.
Wall tie replacement and crack stitching. Most common around Wandsworth & Clapham and Croydon & Bromley.
Leaks, floods and burst pipes. Most common around Richmond & Barnes and Kensington & Chelsea.
Client testimonials
Professional and experienced staff with a vast knowledge and skill set. I commissioned Tapco to complete some damp proofing work, and they discovered other issues that required rectifying during the process. Tapco were equipped and experienced enough to professionally make good all issues in a timely manner and at a competitive price.
Live just outside London? We cover the neighbouring counties too.
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From our offices in Thames Ditton and Esher, our surveyors cover London and the surrounding counties, providing fast response times for residential and commercial properties alike.
We regularly work with:
Whether your property requires a damp survey, timber inspection or basement waterproofing system, our experienced team is ready to help.
Our certifications reflect our commitment to the highest standards of work and quality.
Why Tapco
Established in 1971
Choosing Tapco HomeDry means choosing a company with a proven history of protecting properties across the South East.
We believe every property deserves an individual assessment. That’s why our recommendations are based on what your building genuinely needs, not unnecessary treatments.
Tapco (Preservation) Ltd is an Introducer Appointed Representative (Financial Services Register No. 423558) of Phoenix Financial Consultants Limited (Phoenix). Phoenix is a credit broker, not a lender. Phoenix is authorised and regulated by the Financial Conduct Authority (FRN: 539195), and offers finance from its panel of lenders. All finance subject to status and credit checks.
