It's one of the perennial homeowner complaints. Everything else is neatly painted and looks great, but the garage floor is a greasy, spotted and disgusting mess. Many homeowners try to solve the problem by cleaning the floor as best they can and then rolling on a nice shiny, gray coat of oil-based paint. The floor looks great until a car with hot tires literally peels the paint off, or moisture vapor released from the ground passes through the concrete floor and lifts the paint off. The result of all this wasted effort and money is a garage floor that looks no better than it did before. If this describes your situation, we have some news that might help.
Garage floor coatings fail for a number of reasons. First, the floor is usually not clean enough to receive a coating. Years of grime have to be removed using solvents and proprietary cleaners. These are sold at paint stores, hardware stores, home centers and industrial supply houses. If the floor is really filthy, consider pressure washing. Rent a machine that produces at least 1,200 to 2,000 psi. Also buy some grease-cutting detergent at the rental store. Along similar lines, you might consider a steam cleaner if a pressure washer is unavailable.
Another problem is moisture vapor. Moisture vapor from the ground works from below to loosen the coating's bond with the concrete. In the case of alkyd paints (also called oil-based paints), the moisture will react with the alkaline materials in the concrete and form a soap. This process is called saponification. The soap loosens the paint's bond with the concrete. Never use alkyd or modified alkyd paints on concrete, no matter what the clerk at the hardware store says.
Finally, a car's tires are hot when it pulls into the garage. In the summer, the tires may be even too hot to touch. The heat can actually melt the paint and—combined with the pressure the car applies on the tires—even peel the paint. This is known, appropriately, as hot-tire pickup. Fortunately, there are ways to beat all these problems.
New Formulas to the Rescue
Paint manufacturers have recognized these problems and have come to the rescue with new formulations. But a word of advice: If your garage floor sees heavy water leakage, if it's badly cracked or if it's damp and slimy all summer, don't apply any coating. In those cases, you're better off simply keeping it as clean as you can and then calling it quits.
But about those new formulations. One is Epoxy Shield garage floor paint. It's a waterborne coating consisting of epoxy and acrylic resins with color chips that you sprinkle over it while the coating is wet. Its manufacturer says it is specifically formulated to withstand hot-tire pickup, moisture vapor and attack by solvents and chemicals that drip from a car or come in on the car's tires. It comes as a kit that consists of a cleaner-degreaser, two paint components that you mix together and nonskid color chips. First clean and degrease the floor, then mix the two-part coating together and roll it on. And finish up by broadcasting the nonskid chips onto the coating while it is still wet. The manufacturer says you can walk on the surface in four hours and drive on it after seven days when it is fully cured. The kit costs about $60 at home centers. For information, contact Epoxi Tech, 8 Brush St., Pontiac, MI 48341; 888-683-5667.
It's a little known fact in the northern part of the United States, but you can stain masonry, much like you stain wood. The practice is widely used down south, but not so much up north, probably owing to the beating that concrete takes from snow, ice and rock salt.
Like wood stains, masonry stains are less viscous than paints. They soak into the masonry and don't form a film the way paint does. Unlike film-forming coatings, stains won't make your garage floor feel like the deck of an aircraft carrier. Because of this, stains are somewhat more forgiving and are easier to apply and to reapply as they wear off and become dirty. One of the oldest (perhaps the oldest) masonry stains available is H&C, now owned by Sherwin-Williams and sold at that company's paint stores. This venerable brand has been used in the southern United States for many years, and it's available in a wide range of colors and it can be tinted to any color you prefer. It's available in two formulations: a solvent-base (that is unavailable in California) and a waterborne acrylic available nationwide. The solvent-based formulation, shown on the left, is the tougher one, so if you have both available where you live, choose that unless you're very sensitive to solvent fumes, in which case you should go with the waterborne acrylic. Anyway, homeowners who are used to house paints should have no trouble applying either and cleaning up afterward. First, apply some H&C cleaner degreaser—a mixture of heavy—duty detergent and phosphoric acid. You simply sprinkle the stuff on the garage floor with a watering can, work it in with a broom and let it foam the floor clean. Then rinse the floor and let it dry. The stain is applied with a roller. It's ready for foot traffic in one hour and car traffic in 72 to 96 hours depending on temperature and humidity. A gallon of either H&C stain costs about $20 to 25 at Sherwin-Williams paint stores. Contact Sherwin-Williams, Paint Stores Group, 101 Prospect Ave. N.W., Cleveland, OH 44115; 800-867-8246.
Regardless of what you do with your garage floor, remember that the coating is only as good as its preparation. The surface has to be clean and dry before you do anything. Walls, doors and thresholds have to be protected with masking tape. Take precautions to keep kids and pets off the surface, or you'll have a real mess on your hands—and they'll have one on their feet.
Copyright © Popular Mechanics 2001. Reprinted by permission.