Remove all dirt, wax, dust, mildew, and loose or scaling material with a scraper, wire brush, or stiff bristle brush. Masonry surface must be dry and free of dirt, wax, dust, mildew, and loose or scaling material. For proper penetration and adhesion to extremely smooth bare concrete floors, use muriatic acid. Rinse thoroughly (pressure wash for best results). Allow to dry thoroughly according to manufacturer’s directions. If using a pressure washer, do not use on a pressure setting above 12.06 MPa (1750 PSI) to avoid damaging the concrete. Remember, concrete acts like a stone sponge. Pressure washing and general cleaning may trap residual moisture in the concrete. To check for trapped moisture, tape a 12 po x 12 po (12 in x 12 in) piece of 3 mil plastic or aluminum foil tightly on all four edges to the surface. Remove it after 24 hours. If the floor side of the plastic or foil is damp, allow additional drying and repeat the test.
EFFLORESCENCE, a white, powdery, crystal-like deposit visible on the masonry surface, must be removed. Muriatic acid, used according to manufacturer’s directions, is effective efflorescence removal agent. All masonry surfaces are subject to occurrences of efflorescence. Properly prepared concrete should look and feel like medium grit sandpaper. If concrete remains smooth, repeat muriatic acid procedure. Test concrete porosity by sprinkling a few drops of water onto the surface in several areas. If the water is readily absorbed, you are ready to paint. If it beads or lays on the surface additional cleaning is needed. Rinse thoroughly with clean water and allow to dry for 24 hours. NOTE: Rinse muriatic acid solution thoroughly. Muriatic acid solution allowed to dry on the masonry surface will prevent proper penetration and curing of the Sikagard®-217 Wet Look.
New concrete and freshly applied Portland cement based patching compounds must be cured for a minimum of 24 hours prior to application of Sikagard®-217 Wet Look. Patch all holes and cracks with a suitable cement based patching compound. Be sure to smooth the patch evenly. Allow the patched area to dry thoroughly.
Previously painted masonry surfaces: In addition to normal surface preparation old glossy surface must have the gloss removed by using sandpaper. Remove all sanding dust with a vacuum or tack cloth.