Many products can be applied to slightly damp masonry, but standing water or active leaks must be resolved first. The surface should be clean, stable and free from loose coatings before application.
How Expansion Joint Components Support Brick and Block Construction
Damp proof paint provides a protective coating designed to reduce moisture penetration through masonry and prepared surfaces. Typically applied to internal walls, floors, and occasionally external substrates, these products create a waterproof or vapour-resistant barrier that helps prevent damp patches, staining, and damage to decorative finishes. Used as part of wider damp management work, damp proof paint is commonly applied to brick, concrete,render, plaster and cement-based surfaces where moisture ingress has previously caused issues or where additional protection is required before redecoration. When combined with preparation materials found within Damp Proofing, surfaces can be sealed effectively before plastering or finishing work begins.
In refurbishment and repair projects, damp proof paint is often applied beneath plaster or decorative coatings to block residual moisture and prevent it affecting finished surfaces. It is also used on floors as a liquid damp proof membrane prior to installing coverings, working alongside materials from Floor Levelling Compounds to create a stable, dry base. In kitchens, bathrooms and utility areas, it may be used beneath tiling systems alongside adhesives and products from Tile Adhesives & Grouts, helping reduce the risk of moisture transfer behind tiles. Some formulations are suitable for basements, garages and below-ground spaces when used as part of a layered waterproofing approach that includes solutions available within Waterproofing & Tanking.
Most damp proof paints form a continuous membrane once cured, limiting water vapour transmission while remaining compatible with standard decorative paints once dry. Application is typically by brush or roller in two coats to achieve the specified coverage rate, with surfaces requiring thorough cleaning and removal of loose material beforehand. Water based and solvent free options are widely available, offering low odour application and quicker drying times. By reducing moisture movement through walls and floors, these coatings help maintain plaster integrity, minimise mould growth caused by persistent dampness, and support longer lasting decorative finishes without complex installation methods.
Damp Proof Paint FAQ's
Yes. Damp proof paint helps block residual moisture but is not a substitute for repairing leaks, failed damp proof courses or ventilation issues.
Most manufacturers recommend two coats applied at the specified coverage rate to create a continuous moisture barrier.
A brush or medium-pile roller is commonly used, along with surface preparation tools such as scrapers, wire brushes and cleaning solutions to remove debris or mould before coating.
Any tears or punctures should be repaired using suitable sealing tape or patches before concrete is poured, as even small openings can allow moisture to pass through over time.