Wilko Damp Seal eliminates stains n damp interior walls and ceilings*. It helps to stop discolouration on walls affected by damp penetration, and can also be used as a primer, sealer or finish. It dries to a matt, even-tone finish in 16-24 hours, perfect for overpainting with your chosen colour. The contents of this can will cover approximately 3m2**.*Although suitable for use over damp, this product does not replace the need to repair any structural faults that allow damp to penetrate into the fabric of the walls. **Approximate coverage depends on the nature and porosity of the surface.