Polycell damp seal has been specially formulated to seal patches of penetrating damp on interior walls and ceilings in just one coat preventing them from showing through and spoiling decorations damp seal has a matt white finish that can be over painted or wallpapered if required prevents damp from showing through and spoiling decoration seals patches of penetrating damp on interior walls and ceilings in just one coat touch dry in 4 hours depending on conditions for plaster cement and stone