Stained concrete floors are a popular surface finish in modern architecture. The very first step to stain a floor is thorough preparation. The surface must be meticulously clean. More important, there must not be any interference with the chemical reaction between the stain molecules and the lime in concrete. This reaction is what bonds the materials and sets the color. Use these easy guidelines to prepare a concrete floor for staining.
Sweep and mop the concrete floor with soapy water. Rinse until all soap is removed and allow complete drying. Examine the cleaned floor for any problem areas. Note each type of flaw and identify if it is a crack, spilled paint, a grease spot or other blemish
Drizzle heavy-duty detergent on grease spots and rub with a scrub brush. Wipe repeatedly with a clean damp sponge, rinsing thoroughly between each swipe. Let the area dry and check that the spot has been eliminated. Remove more stubborn grease stains by scrubbing the area with a concrete degreaser liquid purchased from a home improvement retailer.
Attempt to lift dried latex paint spills off the concrete floor with a scraper. Use paint stripper for other types of paint spots. Rub the spots with paint stripper repeatedly until all residue is eliminated.
Fill cracks with patching material that is a concrete acrylic mix with a low-shrinkage warranty. Check the label to verify the patch will absorb acid stain to ensure color blending on the finished floor.
Sand the entire floor surface with a concrete floor grinder. Use a fine-grade abrasive head on the machine to remove a thin top layer where sealants or grime may have penetrated the concrete surface.
Use a shop-vac to suck up dust and debris. Wash the floor with a clean wet mop, rinsing repeatedly until the floor is completely free of particles. Allow sufficient time for thorough drying before stain application.