Megaseal is a heavy-duty tanking membrane, providing a 100% watertight seal that is clearly visible when applied. Drying to a thick, grey membrane, its elastic property allows for movement in walls and floors, but bonds any loose-surface elements to a stable finish ready for tiling. Not just for wetrooms! Megaseal is an extremely versatile material and can be used as a damp proof membrane in many situations such as garage and shed walls and for tanking out basements. Coverage: approx. 4m²/tub (based on 2 coat tanking).