Applying Sealers
Before applying sealer to stamped concrete, the surface must be clean and dry to ensure good adhesion. Also, you should allow the concrete to cure sufficiently — generally several weeks after placement, depending on weather conditions. With stamped concrete, it’s especially important to make sure the surface is free of moisture in low spots of the stamp pattern, where water may accumulate.
There are several tools you can use to apply sealer to stamped concrete, depending on the product you’re using. Pump-up or low-pressure sprayers are best for applying one-part, solvent-based sealers with a solids content below 35%. Airless, or low-pressure high-volume (LPHV) sprayers, can handle both water- and solvent-based sealers and permit very controlled application rates, allowing large areas to be sealed in the shortest time. You can also apply water- or solvent-based sealers with a paint-type roller. To work the sealer into the textured surface and stamp pattern depressions, be sure to use a roller with a fairly thick nap (about 3/8 inch). One of the best application techniques when sealing stamped or textured surfaces is to combine spraying followed back rolling to keep the sealer from settling in low spots and to help distribute the sealer uniformly.
Stamped concrete sealer dos and don’ts
- DON’T apply the sealer too thickly, or it will just lie or puddle on the surface rather than penetrate. Acrylic sealers are designed to go down very thinly, at thicknesses of only 1 to 2 mils.
- DO apply sealer in two thin coats rather than one thick heavy coat to achieve more uniform coverage.
- DON’T apply a solvent-based sealer over a water-based product because the solvent can eat or soften the existing water-based sealer.
- DO refer to the sealer manufacturer’s application guidelines for specifics on surface preparation, recommended application tools, and dry times between coats.
