Stained Concrete Is Not...Stained ConcreteToday, there is no excuse for that gray concrete slab. New techniques are coming down the road--and being improved--to make concrete look less like concrete. One method is stamped concrete. But stamped concrete only affects pattern and texture, not color. Staining imbues your concrete with a huge variety of colors.
Stained concrete is a misnomer. When I think of "stained," I think of a coffee cup spilling on a white sofa. But concrete stain is actually a chemical reaction between the acid stain and the cement within the concrete mix. This bears emphasizing. Concrete is made of both aggregate (rocks) and the binding cement. Because the stain works through a chemical reaction between the stain and cement, the aggregate will not stain.
Process in a NutshellConcrete staining is not the same as adding pigment to wet concrete. The process is performed on cured, hardened concrete, and it can be done by the homeowner.
First, you clean the surface. You'll want to use an organic degreaser at medium strength. Note that because this is a chemical reaction, surfaces previously treated with muriatic acid or otherwise acid-etched cannot be stained. Imperfections in the concrete (that is, the other kind of "stains") will show through. Concrete stain is not a cover-all. Also, you may need to lightly sand down the concrete to open up the surface.
Concrete stain can be applied in many ways (mops, brushes, rollers), but experts such as Direct Color, Inc. recommend spraying on with an ordinary sprayer such as you might use for herbicides. This provides for a wider, smoother broadcast of the concrete stain.
The stain can be diluted with water, which allows for a lighter application of stain. But if too much water is added, the chemical reaction with the cement will not take place.
What you see at first is not the end color. It takes up to 8 hours for the chemical reaction to take place. Don't walk on the concrete stain because your footprints may end up permanently on your concrete.
Concrete Stain KitsConcrete stain kits are available at your local hardware store. These kits contain everything you need: the stain, sealer, gloves, instructions. (Buy Direct - EPOXYShield Concrete Stain Kits - Sandstone Tint)
Keep in mind, though, that they may not cover a lot of square footage: perhaps as little as 200-400 square feet. However, a concrete stain kit may be a good way to experiment with a little-used section of patio or even the concrete pad underneath your AC unit--before moving to the bigger areas such as driveway.