DRYLOK® Clear Masonry Waterproofer may be applied on a slightly damp surface, but best results are obtained when the surface is dry, clean, and free of grease, oil, form release compound, and paint. Remove dust, dirt, and any loose or broken mortar with a wire brush*. Old paint in poor condition should be removed by wire-brushing, sandblasting or other suitable methods. If you see white, powdery, crystal-like deposits on the surface, they are naturally-occurring, water-soluble salt compounds in the masonry, pushed out by water intrusion. When the water evaporates, the salt residue remains. This effect is called efflorescence and, because it prevents DRYLOK® Clear Masonry Waterproofer from properly bonding to the surface, it must be removed. Treat it with DRYLOK® Etch®** (liquid or powder formula) or muriatic acid according to the manufacturer's directions. Proceed to rinse and allow the surface to dry. Since efflorescence occurs naturally, we cannot warrant against it reoccurring.
Patch all cracks and holes with DRYLOK® Fast Plug®. Wet the surface to be patched and, so DRYLOK® can better anchor itself into the wall, back chisel the areas to be patched into shapes like an inverted “V”. Apply and smooth the patch so it's even with the surface around it. As DRYLOK® Fast Plug® sets rapidly, mix only what you'll use in 3 to 5 minutes. Also, be sure to seal the area where the floor and wall meet. Often, when concrete floors cure, they shrink and pull away from the wall, creating a space where water can enter.
Floor Preparation
Highly troweled or extremely smooth concrete floors must be acid etched or mechanically abraded to achieve the proper profile. Treat the surface with DRYLOK® Etch®** (liquid or powdered) or muriatic acid, according to the manufacturer’s directions. A properly prepared concrete floor should look and feel like medium grit sandpaper. Repeat the etching procedure until the proper texture is achieved.
Test the concrete’s porosity and check for residual sealers by sprinkling a few drops of water on surface. If the water does not readily penetrate into the prepared concrete, additional acid etching is required. Remove any residual acid etching material from the surface, rinse it thoroughly and allow it to dry.
To check for trapped moisture, affix a 12” x 12” piece of 3 mil plastic or aluminum foil to the surface, taping it tightly along all four edges. Remove it after 24 hours. If the surface side of the plastic or foil is damp, allow additional drying and repeat the test.