Damp Proofing London — Waterproofing Specialists Across the Capital
Covers Of London provides damp proofing across London for residential and commercial properties of every age and construction type. Based in Hackney, our team diagnoses and treats rising damp, penetrating damp, condensation, and below-ground water ingress — from Victorian terraces in Islington to converted warehouses in Shoreditch and family homes across Essex and Hertfordshire.
30+
YEARS IN THE TRADE
3,500+
PROJECTS COMPLETED
Free
DAMP SURVEYS
10yr
WORK GUARANTEE
WHY LONDON PROPERTIES NEED DAMP PROOFING
Damp Proofing Services for London Properties
Much of London sits on clay-heavy soil with a naturally high water table. Add to that an ageing housing stock — millions of properties built before the 1920s, many without an effective damp proof course — and you have the conditions for persistent moisture problems that won’t resolve themselves.
Damp left unaddressed doesn’t just ruin plasterwork. It rots timber, degrades masonry, and creates conditions for mould that can affect the health of everyone living in the property. The longer it’s left, the more it costs to put right.
We carry out a full diagnostic survey before quoting any work. That means calibrated moisture readings, a thorough internal and external inspection, and — where the source of the problem isn’t immediately clear — thermal imaging and drone inspection of the roof and external walls. We identify the type of damp, trace it back to the source, and recommend the right treatment. Not an upsell. The right treatment.
TYPES OF DAMP WE TREAT
Rising Damp, Penetrating Damp & Condensation
Each form of damp has a different cause and requires a different treatment. Correct diagnosis is the single most important step in the process.
Rising Damp Treatment
Rising damp happens when moisture from the ground travels upwards through walls by capillary action. It’s most common in older London properties where the original damp proof course has failed or was never installed. You’ll often spot a horizontal tide mark across internal walls, sometimes with white salt deposits on the plaster.
We treat rising damp by installing a new chemical damp proof course — a silicone-based injection that forms a permanent barrier within the masonry. Affected plaster is stripped back, contaminated material removed, and the walls are then re-rendered using a salt-retardant specification before being left ready for decoration.
Penetrating Damp Repairs
Penetrating damp enters a building horizontally — through external walls, around window frames, via defective guttering, or from cracked render and deteriorated pointing. It can appear at any height on the wall and is often worse on elevations exposed to prevailing rain.
The fix depends on the cause. It might involve repointing brickwork, repairing or replacing external render, overhauling gutters and downpipes, or applying a breathable water-repellent treatment to the external face. We repair the source and then deal with the internal damage — which typically means stripping damp plaster and re-finishing once the wall has dried out sufficiently.
Condensation Control & Ventilation
Condensation is the most widespread cause of damp in London homes — and the one most frequently misdiagnosed as rising or penetrating damp. It occurs when warm moist air meets cold surfaces, particularly in bathrooms, kitchens, and poorly ventilated bedrooms. The result is black mould, streaming windows, and a musty smell that no amount of repainting will eliminate.
We install positive input ventilation (PIV) systems, extractor fans, and other mechanical ventilation solutions tailored to the property. In some cases, improving insulation on cold bridging areas resolves the issue entirely. We always confirm the diagnosis before recommending treatment — misidentifying condensation as structural damp leads to unnecessary and expensive works.
Basement Waterproofing & Tanking
Below-ground spaces present their own set of challenges. Water pressure from saturated ground pushes moisture through basement walls and floors, and standard damp proofing methods aren’t sufficient to deal with it.
We install structural waterproofing systems in accordance with BS8102 — the British Standard for protection of below-ground structures against water ingress. That includes cementitious tanking (Type A) for lower-risk situations and cavity drain membrane systems (Type C) with sump and pump installations where higher volumes of groundwater need to be managed. The right system depends on the property, the ground conditions, and how the space will be used.
We’ve tanked basements and cellars across East London, North London, and into Essex — everything from compact Victorian cellars in Stoke Newington to large commercial undercrofts in the City.
Damp Proof Course Installation & Renewal
A functioning damp proof course is the primary defence against rising damp. In properties built before the 1870s, there may never have been one. In those built between the 1870s and the 1950s, the original DPC — often slate, bitumen felt, or engineering brick — may well have deteriorated beyond usefulness.
We install chemical injection damp proof courses using silicone-based cream systems injected into the mortar bed at low level. The material diffuses into the masonry and cures to form an impermeable barrier. It’s a proven, widely accepted treatment recognised by mortgage lenders and building surveyors.
Where the external ground level has been raised above the DPC line — a common issue in London where paths and patios have been laid over the years — we’ll advise on the most practical remedial approach, whether that’s lowering the ground level, installing a French drain, or applying a tanking-grade treatment to the affected section of wall.
DAMP IN PERIOD PROPERTIES
Damp Proofing for Victorian & Period Properties
A large portion of London’s housing stock dates from the Victorian and Edwardian eras. These properties were built with solid walls — typically a single skin of brick — and were designed to manage moisture through breathability rather than barrier membranes. That approach worked well enough for 100 years. But modifications since then — cement renders over the original lime mortar, impermeable paints, raised external ground levels, sealed fireplaces — have disrupted that natural moisture balance.
The result is trapped moisture that has nowhere to go. We see this regularly across Hackney, Clapton, Stoke Newington, Dalston, and right through the inner boroughs. Period properties in Islington, Camden, and Southwark are particularly affected.
The wrong treatment makes things worse. Injecting a chemical DPC into a solid-walled property that actually has a condensation problem — or coating the inside of a breathable brick wall with a non-breathable tanking slurry — traps moisture and accelerates decay. We assess the building as a whole before prescribing anything, and where breathable materials are needed, that’s what we use. Lime-based renders, natural hydraulic lime plasters, and vapour-permeable coatings all have their place in period property damp treatment.
OUR PROCESS
Our Damp Survey & Diagnosis Process
01
Full Property Survey
We attend your property and conduct a thorough inspection — internal and external — using calibrated moisture meters and, where needed, thermal imaging equipment. We check wall moisture levels, plaster condition, ventilation, external ground levels, and any obvious sources of water ingress. The survey is free and comes with no obligation.
02
Written Report & Quotation
You receive a written report confirming the type of damp, the cause, and our recommended treatment — along with an itemised, fixed-price quotation. If we don’t think treatment is needed, or if the issue can be resolved with a minor maintenance item rather than a full damp proofing job, we’ll tell you. The price we quote is the price you pay.
03
Treatment & Guarantee
Our team carries out the treatment at a time that works for you. Every person on site works directly for us — we don’t sub-contract damp proofing work to third parties. On completion, you receive a written guarantee for the works carried out. We hold full public liability insurance, and our treatments are carried out to British Standards using materials from established industry suppliers.
Service Areas
Damp Proofing Across London, Essex & Hertfordshire
We’re based in Hackney, East London, and carry out damp proofing work across the capital and into the surrounding counties. We know the building types, ground conditions, and common moisture problems specific to each area — from the clay soils of South London to the higher water tables around the Lea Valley and Thames basin.
Hackney
Islington
Tower Hamlets
Camden
Southwark
Lambeth
Walthamstow
Stratford
Enfield
Romford
Brentwood
Watford
St Albans
Chelmsford
All London Boroughs →
Why Choose Covers Of London for Damp Proofing
Damp proofing is not a one-size-fits-all trade. The wrong diagnosis leads to the wrong treatment, and that means wasted money and a problem that comes back. We’ve seen it dozens of times — properties where a previous contractor has injected a chemical DPC when the actual issue was condensation, or where tanking slurry has been applied over a wall that was wet because of a leaking gutter two metres above.
We take the time to get the diagnosis right. That’s what separates a proper damp proofing contractor from someone who turns up with a drill and a tube of cream.
Every person on your project works directly for us. We don’t sub-contract damp proofing work. Our quotes are fixed and itemised, our work is guaranteed in writing, and we carry full public liability insurance on every job. If the problem turns out to be simpler than expected — a blocked air brick, a missing roof tile — we’ll tell you that too, rather than selling you a treatment you don’t need.
Customer Reviews
What our customers say
FAQS
Damp Proofing — Frequently Asked Questions
How much does damp proofing cost in London?
Costs vary depending on the type of damp, the extent of affected area, and the treatment method required. A chemical DPC injection for a single room might start from around £500–£1,200. Basement tanking typically costs from £100–£150 per square metre. We provide free surveys and fixed-price quotations before any work begins, so there are no surprises.
What are the signs of rising damp?
The most common indicators include a horizontal tide mark on internal walls — usually up to about one metre from floor level — along with peeling or bubbling paint, white salt deposits on the plaster surface, damp or deteriorating skirting boards, and a persistent musty smell. If you notice any of these, we’d recommend arranging a professional damp survey.
What is the difference between rising damp and penetrating damp?
Rising damp occurs when moisture from the ground is drawn upwards through walls by capillary action — typically where the damp proof course has failed or was never installed. Penetrating damp enters horizontally through walls, roofs, or around windows and doors, usually caused by defective guttering, cracked render, or failed pointing. The treatments are different for each, which is why a proper survey matters.
Can you damp proof a Victorian property?
Yes — a significant proportion of our work involves Victorian and Edwardian properties. These buildings were often constructed without a DPC, or the original has degraded over time. We use treatment methods appropriate to older construction, including breathable lime-based materials where solid walls need to retain their natural moisture management.
Do you offer a guarantee on damp proofing work?
All damp proofing treatments we carry out come with a written workmanship guarantee of up to 10 years. We hold full public liability insurance on every project, and our treatments are carried out to British Standards using materials from established industry suppliers.
How long does damp proofing take?
A standard DPC injection and replaster on a single room typically takes 2–3 working days. Basement tanking projects are more involved and can take 1–2 weeks depending on the size and condition of the space. Estimated timescales are included in every quotation.
Do I need a damp survey before treatment?
Always. Accurate diagnosis is critical — misidentifying the type of damp leads to the wrong treatment, wasted money, and the problem returning. We carry out a thorough damp survey using calibrated moisture meters and provide a clear written report before recommending any work.
What areas do you cover?
We are based in Hackney, East London, and carry out damp proofing work across every London borough. We also cover surrounding areas in Essex and Hertfordshire, including Romford, Brentwood, Chelmsford, Enfield, Watford, and St Albans.
Get a free damp proofing quote
Whether you’ve spotted the first signs of damp or you’re dealing with a basement that floods every winter, we’re ready to help. Leave your details and we’ll arrange a free survey — most inspections can be carried out within 48 hours of your call.
Get a Free Damp Proofing Quote Today
If you’ve spotted damp patches, mould, peeling plaster, or anything else that suggests moisture is getting into your property, don’t leave it. Call us on 0208 064 3801 or fill in the form above and we’ll arrange a free survey and detailed quotation. Most inspections are carried out within 48 hours.