Floor Finish Overview
Applying an epoxy coating to a concrete floor is as easy as painting walls, but as with painting, the success is in the prep work. Once the calculations, color choices, and cleaning are taken care of, the actual application will seem like the easiest part.
To bond well, epoxy requires an even, slightly rough, and totally clean surface. That means patching any potholes and cracks and allowing them to cure fully. Concrete must be at least 60 days old and not sealed for the epoxy to adhere. You can tell if your floor already has a sealer if water beads on it or if you get to Step 2 in this process and the etching solution doesn't foam; if that's the case, you'll need to take off the sealer with a chemical stripper or a special machine. (Painted floors can be recoated if there's no peeling.)
Stripping the floor, however, does not clean it. Any grease or dirt will compromise the epoxy adhesion, so cleaning and etching is a step that should not be rushed. Different manufacturers offer different types of cleaners, so check out the ingredients before you choose what type is best for you. Chemical cleaners vary widely, from harsh degreasers and etchers to safer but less effective organics. You can cut down on the elbow grease by renting a machine called a floor maintainer for about $40 a day.
Epoxy coatings typically come in kits with everything you need. Once you choose one, determine if you'll need to order extra supplies. Manufacturers may suggest two coats of the epoxy paint and top coat, but most standard kits only supply enough for one coat. If you choose to add color flakes, which will help hide concrete's inherent imperfections, determine how heavily you'll broadcast them across the floor so you don't come up short. Also, if your garage's foundation rises above grade at the bottom of the walls, you may want to consider coating another few inches up the vertical surfaces to make cleaning the garage easier. Then decide if you want to include an antiskid additive, granules that give the finished floor a sandpaperlike surface. This may be a good option in rainy or ice-prone regions.
Once the floor is clean and ready for its coating, it all comes down to timing. Choose a day to do the work when the concrete won't be damp from rainy weather and when the temperature is between 50 and 80 degrees; otherwise the application can bubble and peel. Then, once you mix the epoxy paint and hardener, you only have about 2 hours to work with it, so you'll need to plan out in advance how best to paint yourself out of the garage, starting in a back corner. The hardest part is waiting: The typical drying time between each step is 12 to 24 hours. And once the whole floor is done, you still have to hold off parking the car on it for another 72 hours.