Damp Proof 4LAn acrylic brush on membrane that will prevent rising damp, efflorescence and will resist negative hydrostatic pressure. It has excellent adhesion to most substrates including brick, masonry, concrete block, concrete, stone and timber and is simple to use by brush or roller. Dunlop Damp Proof Moisture Barrier is safe to use and can be overcoated using almost any decorative paint Prevents raising damp, efflorescence, negative hydrostatic pressure High