Nearly everyone who has a garage has wanted to paint the floor, because let's face it – everything that you want to show off to your buddies is pretty much located in the garage. Many times, people try to paint the floor of their garage with oil based paint and it doesn't hold for several reasons, heat from car tires or moisture vapor or a cleaning job that wasn't done thoroughly. No matter how hard you try to clean your floor before painting there is a good chance that residue that is left over will keep whatever paint you choose from bonding properly.
If you really want to clean the years of grime, dirt and other liquids that make up the surface of your garage you'll need specialized proprietary cleaners and solvents that you can get at most hardware stores. You may also need a pressure washer or a rented floor scrubber with brushes to prepare your floor for painting. Make sure when you get your scrubber that you get detergent for it as well.
Before you buy anything at all, however, you want to test your garage floor's moisture. Put a plastic bag on the ground and tape it down on all edges. Then, leave it for 24 hours. After the twenty four hours have passed pick the bag up and see if there is any moisture underneath. If there is, then the water moisture will prevent any paints or epoxies from bonding to the concrete. You will have to consult with a professional to learn how to solve this problem before you paint.
Use either an Epoxy or one of the new formulas that they are coming out with. Don't use alkyd or modified alkyd paints on the concrete. One Epoxy is Epoxy Shield, which is a mixture of epoxy and acrylic resins. Another alternative is staining your masonry, much as you do with your woodwork. Many states in the southern part of the United States use this method.
We're going to talk about the epoxy method here, recommended because it works well and because it makes the floor of your garage look brilliantly shiny just like the floor of an auto show room. Epoxy is great because it is durable and the coating lasts for a long time. Plus it is resistant to grease and oil, and other stuff that paint wouldn't be able to stand up to. There are a wide variety of colors available.
You're going to spend the entire first day cleaning the floor. You'll need to get rid of all of the oil spots, degreasing the floor and scrubbing it. Also vacuum and rinse it several times. You need to make sure that everything is gone from the floor. You'll then spend the second day filling the cracks that are in the floor and you'll put down the first epoxy coat. A couple of other things to remember is that if you have just barely laid down your concrete slab you need to wait 30-60 days before you are able to paint it. This will give the concrete a chance to cure and dry completely, otherwise you will waste your time painting. Also, if paint is already on the concrete remove it completely, since the epoxy could soften the paint and not let your epoxy bond. One more thing before you begin. Make sure you do this when the temperature is around 60 degrees or more.
Let's talk about what type of epoxy to use. There are three separate types of epoxy, 100 percent solid epoxy, solvent based and water based. There is a clear choice in our opinion since the solid epoxy paints are expensive and hard to work with since they harden almost right away, while the solvent based are extremely hazardous. You have to use a respirator, because the fumes and vapors are extremely dangerous. If you use this type you'll need to take special precautions for airing out the space, as well as keeping pets, kids and neighbors away.
If you don't want to deal with the issues mentioned you can go with a water based epoxy. There are two parts that you mix up just before applying it, containing 40 to 60 percent solids. There aren't any fumes for you to breath with this mixture and you can generally find this type of epoxy at stores like home depot and the like. Get yourself gloves and boots and proper protection and you'll be ready for the first day of applying epoxy.
Okay, so you should have already cleaned the floor thoroughly. On day two you'll put the first coat down on your garage floor. First fill in the cracks and holes with an epoxy filler and use a putty knife (plastic works best) to scrape off the excess and level. Then let your crack fill-ins dry for about four hours. You can mix the epoxy in the meantime. Start with a easy pace, and begin painting. It should take an hour or less to paint a standard size two-car garage.
Next, let the coat dry overnight, or more if the label says to, and add something for non-skid to the second mix of epoxy. This will keep you from slipping if snow of other moisture gets into your garage. Now coat your garage with the second coat, and let it dry for another sixteen to twenty hours before allowing anyone to walk on it.
Those are the basic steps, but of course you'll want to consult with a professional if you have questions or problems. You may even want to hire a professional to do the initial cleaning to make sure it gets done right. Good luck with all your painting projects.