Tape a large square of aluminum foil to the concrete and leave it for a full day. Remove the foil and look for moisture underneath it. Moisture problems are common with concrete, and will prevent the paint from adhering well. If the foil is dry, you can paint. If not, you'll need to eliminate the cause of the moisture before proceeding.
Clean your concrete thoroughly. The cleaner it is, the better the paint will adhere and the better it will look. You can use plain dishsoap and water to clean general dirt. A household cleaner and degreaser will take care of many stains. If needed, you can clean oil with bleach; grease can be absorbed with cat litter. Allow the area to dry completely.
Remove the sealer and previous paint, if needed. The paint will adhere best on a porous surface, so it will not work well if your concrete is too smooth or has a finish. You can find out if the concrete has a finish by sprinkling a few drops of water over the surface. If the water beads, the concrete has a sealer. Sealer can be removed with a chemical stripper or ground down.
Apply painter's tape around areas that you want to protect. For instance, tape the bottom edge of a wall or baseboard if you're painting a floor.
Prime the concrete with a concrete primer using a roller for large areas and a brush for small ones.
Apply a layer of paint using a roller for large areas and a brush for small ones. Be sure to use an appropriate paint; for instance, if you're painting a floor, use floor paint. Look for paints that are designed for concrete. Masonry paint also works well. You'll need two paints in the same color, one lighter than the other. Use the lighter color first. Wait for the paint to dry completely.
Mix the second paint color with glaze according to the instructions on the glaze. Mix enough glaze to cover the entire surface so that you don't have to try to color-match two batches.
Paint the glaze on the concrete in a very thin coat. Work in small patches, as you must add the texture before the glaze dries. There are several ways to add woodgrain texture; one of the easiest is to use a graining tool designed for faux wood painting. Just run the teeth of the tool through the wet paint to remove thin strips of paint, imitating woodgrain. You can also use a coarse-bristled brush. Don't be too tidy or straight; the grain should look wavy and natural. Make sure that all of the grain goes in the same general direction and wipe excess glaze from your tool often. Wait for the glaze to dry.
Add details, if desired. You can use a dark brown paint to add small circles for knots or lines to create the illusion of individual "boards." Wait for the paint to dry.
Coat the concrete with a protective finish to protect both your work and the concrete. Finishes can usually be applied with a roller and brush. There are several appropriate finishes, including acrylic sealers, polyurethane and epoxy-based sealers. Epoxy-baseds sealers are very durable, but may trap water if you have a problem with moisture. Acrylic sealers are simple to use and inexpensive. Polyurethane is a good choice for concrete countertops.
Rochelle Leggett has bachelor's degrees in biopsychology and English and a Master of Library and Information Science. She has been writing for over 15 years and was first published in 2000. She has been employed in academic settings as a librarian and an archivist.
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