Concrete Painting 101

by Paul Bianchina

Whether it’s your garage floor, your patio or some other spot where that concrete slab could use some dressing up, a coat of paint might be just what’s needed.

The trick to a good-looking, long-lasting paint job on concrete is to select the right paint, and don’t skimp on the prep work.EPOXY COATINGS

If you’re looking for the most durable finish for a concrete floor, your best choice is epoxy. Epoxy paints, which commonly come in two parts and are mixed on-site (premixed epoxies are also available), bond strongly to the concrete and resist weathering and abrasion extremely well. If you’re painting your garage floor, epoxy is also the only coating that will effectively resist “hot-tire pickup,” which is a lifting of the paint caused by the heat and pressure of your car’s tires.

Because the epoxy film is thicker than a standard paint film, it also gives you the opportunity to imbed small, colorful, vinyl chips in the finish. These chips give your garage that “showroom” look, and also add a little slip resistance.

Epoxy coatings have some definite drawbacks as well. First of all, they require some fairly extensive preparation work, and cutting corners on the any of the prep will almost certainly lead to a premature failure of the coating. Any cracks in the slab should be repaired, and the floor needs to be thoroughly cleaned and degreased then washed, rinsed and allowed to dry before painting. These steps are more important — and typically more time-consuming — than the actual painting process itself.

Another drawback is that once the two parts of the paint are mixed, you have a pretty short window of time in which to get it on the floor before it begins to harden. You can help speed up the painting process by having one person cut in around the edges while the other one begins rolling. If you’re using the vinyl chips, you’ll also need to stop periodically and sprinkle them on while the coating is wet enough to receive them.

Because of this relatively short application time, it’s difficult to paint more than the equivalent of about a one-car garage at any one time. If you have a larger area than that to do — a typical two-car garage, for example — you may end up with some visible overlap marks.

Epoxy floor paints are often available in do-it-yourself kits that include the two parts of the paint, a bag of vinyl chips, a cleaner/degreaser, and complete instructions. Because the preparation and application steps are so important to get right, some manufacturers also include a how-to video, and it’s well worth watching.

Epoxy paint, as well as complete garage floor and basement floor kits, are available at most home centers and paint stores in several standard colors.

PORCH AND FLOOR ENAMEL

Another option for use on concrete floors is what is commonly known as porch and floor enamel. As the name suggests, these paints — available as both oil-base and water-base — are specially formulated for use on concrete floors that will see light to moderate activity on them. They are not a good option for areas such as commercial shop floors, and since they are not resistant to hot-tire pickup, they shouldn’t be used in a garage either.Porch and floor enamels are premixed, one-part paints that are applied in much the same manner as any other type of paint. You have a much longer open time then you do with epoxy, so painting an entire two- or even three-car garage at one time is not a problem. You will find these paints in both pre-mixed and custom-mixed colors, typically in satin, semi-gloss and gloss sheens.

You still need to do some prep work before painting, but it’s not as extensive as with an epoxy. The floor needs to be clean and dry; heavy grease spots need to be removed; and large cracks should be repaired.

There are a couple of drawbacks to porch and floor enamels as well. In addition to the hot-tire pickup, these types of paints do not bond quite as well to the concrete, so they’re not as durable, especially in high-traffic or high-abrasion areas. The more gloss the finish has, the more abrasion resistance it has as well, but it also becomes more slippery when wet. To counter that slipperiness, you can blend an anti-skid additive into the paint prior to application. Because the paint film is thinner than epoxy, you cannot embed vinyl chips in this type of paint.

Porch and floor enamels, as well as non-skid additives, are available at all home centers and paint stores.Remodeling and repair questions? E-mail Paul at [email protected]. What’s your opinion? Leave your comments below or send a letter to the editor. To contact the writer, click the byline at the top of the story.