Zinsser Gardz is a water based sealer for porous and potential problem surfaces. Gardz is formulated to deeply penetrate and dry to a hard, moisture resistant film that seals and binds down porous, chalky and crumbling surfaces, paints and textured finishes. Gardz dries rock-hard and is clear, water-resistant finish; this protects surfaces from damage during the next redecorating project. Recommended for damaged drywall, new drywall, speckling and joint compound skim coats, plaster, calcimine, un-coated wallpaper, wall-covering adhesive residue, textured paint and more. Repairs torn paper on damaged drywall, eliminates bubbles, seals old wallpaper adhesive. Can be applied to high pH surfaces and can be cleaned up with soap and water. Touch dry - 30mins, hard dry and re-coatable in 3 hours. Coverage - 1Ltr will cover 7 - 10M sq.