Spray-Applied Basement Waterproofing
Spray-Applied Basement Waterproofing Tanking slurry applied by spray: fast, seamless and fully watertight!
Damp walls and ceilings are a clear sign that the original damp proofing was poorly installed or has failed over time. When water is coming in from the surrounding ground, the work has to be done in the basement itself. Internal basement waterproofing with spray-applied tanking slurry is one of the least invasive solutions available, with no need for costly excavation around the outside of your property.
What Is Tanking Slurry?
Tanking slurry is a mineral, cement-based waterproofing mortar modified with polymers. It is applied in thin coats, usually 2–4 mm in total, and bonds permanently to the wall or floor, creating a seamless, watertight barrier that resists moisture and water pressure from the ground. Unlike bitumen or resin coatings, it stays breathable and works well with masonry and concrete, and it can even be tiled over.
We use two main types, depending on the conditions:
- Flexible slurry: accommodates small movements in the structure and bridges hairline cracks.
Rigid slurry: ideal for stable, solid surfaces.
Benefits of Spray Application
- Speed: spraying is much faster than applying by brush or trowel, so your basement is back in use sooner.
- Even coverage: the spray machine applies a consistent layer of material across the whole surface.
- Precision: the slurry gets deep into pores, gaps and uneven areas of the wall, leaving no weak spots.
- No joints: one continuous coating with no seams for water to find.
Is It the Right Solution for Your Basement?
Wet patches on basement walls and floors usually mean water pressure from the ground or rising moisture. Spray-applied tanking slurry is an excellent way to seal the pores in concrete and masonry in these situations. Where water is actively seeping, dripping or running through the wall, the pressure is too high for slurry alone, so we first stop the leaks. In some cases, a cavity drain membrane system may be the better choice, and our surveyors will always tell you honestly which solution suits your property.
How We Carry Out the Work
- Survey and stopping active leaks: we find where water is coming through, remove plaster where needed and seal leaks with fast-setting hydraulic plugging mortar.
- Surface preparation: we remove weak plaster, paint and salt deposits, repair cracks and leave the surface clean, sound and damp, but with no standing water.
- Replacing damaged mortar: if the existing masonry mortar is crumbling or delaminating, we replace it in the damaged areas, or ideally across the whole wall, so that the remaining mortar joints do not deteriorate further and the slurry has a sound, solid base.
- Wall-to-floor junction: we form a fillet or embed a flexible sealing tape at this most vulnerable point.
- Spray application: we apply at least two coats of slurry, around 2–3 mm in total, with the second coat applied once the first has set.
- Floor protection: if the basement will be used, we lay a protective screed over the waterproofed floor.
Safe Working in Damp Basements
Wet walls and floors encourage mould, and its spores are harmful to breathe. During the work, especially when removing old plaster and spraying, our team keeps the area well ventilated and uses proper respiratory protection, keeping your home safe.
Trusted Manufacturers & High-Quality Materials
We use proven products from well-known manufacturers such as Wykamol, Delta, Newton, Biokil and Mapei. Together, they form one complete system that keeps your basement dry for years to come.
Qualified Specialists & a 10-Year Guarantee
Our family-run team holds CSSW qualifications, with a minimum of 10 years’ experience each. We back our work with a 10-year guarantee covering workmanship, plus a QANW Insurance Backed Guarantee that transfers to the new owner if you sell your property. Based in Croydon, we work on domestic and commercial properties across London and the South East.
See What Our Clients Say
We are proud of our 5-star Google rating: see our reviews. If your basement is damp or takes in water, book a survey in our Booking Survey section, or call or message our fully qualified advisors.
