How to Paint a Garage Floor By Applying Epoxy
What's new with garage floor paint: Achieve auto showroom brilliance in one long weekend for less than $500 with epoxy flooring paint.
IntroductionTransform a dull garage floor into a brilliantly colored auto showroom in one long weekend with a durable, professional quality epoxy floor finish.
- Organic vapor/acid respirator
- Paint roller
- Power floor scrubber (rental)
- Rubber boots
- Rubber gloves
- Safety glasses
- Stiff bristle brush
- Wet/Dry Shop Vacuum
- Cleaner/degreaser fluid
- Epoxy crack filler
- Epoxy floor paint
- Muriatic acid
Evaluate your garage floor
If you’re wondering how to paint a garage floor, epoxy is one good option. Garage floor epoxy flooring is a tough, long-lasting coating that you paint onto the concrete. An epoxy garage floor resists grease, oil and many other substances that would ruin ordinary paint. Garage floor epoxy paints clean easily and can be found in a variety of colors (if you look hard enough), so you can keep your garage floor paints sparkling clean and attractive for years.
However, the reality of this challenging project is, one, not all concrete floors will hold epoxy floor coatings, and two, preparing concrete for epoxy floor coatings can be labor intensive and tedious. That said, this story will help you assess your concrete’s condition, show you how to clean and etch it, and demonstrate how to apply an epoxy garage floor coating that will handle car traffic, chemicals, oils, salt and scraping better than any other paint or stain.
As with any other paint job, success with using garage floor paints lies in the prep work. Plan to spend the first day removing oil spots, cleaning/degreasing the floor, etching it with a mild acid, and scrubbing, vacuuming and rinsing (a lot!). Day two is for filling cracks and applying the first coat of epoxy flooring, which is followed by a second coat on day three. This job doesn’t require many special tools. But to do the best job (and save your back), we recommend that you rent a walk-behind power floor scrubber (Photo 2) with a stiff brush attachment. Brushes work better than scrubbing pads on concrete, but buy two pads if a brush isn’t available. Also, rent a wet vacuum if you don’t own or have access to one.
Test Your Concrete for Moisture
Lift the corner of a plastic bag that’s been taped to the garage floor for 24 hours. If it’s dry underneath, you can proceed with a garage floor paints epoxy coating. If you see moisture under the plastic, don’t coat the floor with epoxy; water pressure will break the bond.
Analyze the floor and weather before you even consider an epoxy garage floor, test to determine if dampness is coming up through the concrete from the ground. If moisture is evident, your floor isn’t suitable for epoxy. Also, forgo the project if a concrete sealer was previously used (you’ll know a sealer has been used if water beads up when applied to the surface). If you’re dealing with a new slab, you must wait a minimum of 28 days, preferably two months, for the floor to cure and dry thoroughly before applying a epoxy flooring. And if you’re dealing with a previously painted floor, the best advice is to remove the paint, especially when you’re applying a solvent-based epoxy garage flooring paint that could soften any that remains.
If your concrete passed these tests, make sure the weekend weather passes, too. The temperature of the concrete must be a minimum of 55 degrees F, with an air temperature between 60 and 90 degrees for optimum garage floor epoxy curing/drying.
Project step-by-step (10)
Scrub oil stains
To begin, use a flat-edged shovel or scraper to loosen hardened surface debris, then sweep it out with a stiff-bristle garage broom. Dip a stiff-bristle brush into a cleaner/degreaser and scrub oil stains aggressively. Wipe up with cotton rags or paper shop towels. Repeat the procedure until the greasy feel is gone and water droplets no longer bead up on the surface before your epoxy garage floor project. Next, mix up a 5-gallon batch of water and concrete cleaner/degreaser according to label directions (found at home centers and hardware stores).
Use an electric floor scrubber
Wet the entire floor with a hose, then scrub back and forth using an electric floor scrubber with a brush attachment (or a coarse scrubbing pad if a brush attachment is unavailable). Pour cleaner/degreaser mixture onto the floor as you go to keep suds going on your epoxy garage floors paint task.
Once spots are cleaned, power-scrub the entire floor. To clean a two-car garage floor, plan on scrubbing for 20 to 30 minutes (keep the floor wet at all times). Make sure you scrub with a stiff-bristle hand brush along the walls and in the corners where the machine cannot reach.
Vacuum the wet floor
Push a rubber squeegee along the floor and pool the soap mixture into smaller areas. Vacuum up the solution for proper disposal.
Once you’re satisfied with dirt removal, vacuum up the cleaner for proper disposal. Don’t just wash the product down the drive into the storm sewer. The environmental effects of cleaning products can vary widely. Check the product label or call the manufacturer for the proper waste disposal method. We looked up the Material Safety Data Sheet for the product we used (made by Behr) on the website www.msdssearch.com and learned we could pour the waste into the “sanitary sewer” (toilet). Also check the label or call the manufacturer for instructions on safe disposal of all leftover product and containers. When in doubt, call your city or county environmental office.
Sprinkle the floor with acid/water solution
Pour 12 ozs. from a bottle of 32 percent muriatic acid (common formulation) into a gallon of water (1 part acid to 10 parts water) in a plastic sprinkler can, then sprinkle evenly over a 10 x 10-ft. area.
Before etching concrete with the acid solution, hose down your entire driveway and several feet beyond the sides of the drive. This aids in the final rinse out of the garage so the material will flow more easily down the driveway. Now sprinkle the 10:1 ratio of water to muriatic acid mixture and power-scrub the floor (with a rinsed brush attachment or new pad).
When you’re finished, take your hose and nozzle end and flood the floor with water, spraying the material out of the garage for a good 10 minutes (diluted muriatic acid can be rinsed with large volumes of water into a storm sewer, according to the manufacturer). Rinse off the power scrubber brush/pad, then scrub the wet floor one last time for 5 to 10 minutes.
Finally, rinse out the entire floor and driveway two to three more times. The concrete surface should now feel like fine-grit sandpaper. If not, you need to repeat the acid washing. Finally, to speed the drying process, squeegee out any remaining pooled water, and take a rag and dry any remaining spots, cracks or chipped areas. Leave the garage door open overnight to speed drying during the epoxy floors project.
Power scrub the floor again
Power-scrub the 10 x 10-ft. area for 5 to 10 minutes. Repeat sprinkling/ scrubbing for each 100-sq.-ft. section, making sure the entire floor stays wet. When you’re done, spray a large volume of water on the floor to flush the residue out. Power scrub again, then rinse two or three times. Let the floor dry overnight, until it appears white.
Always add acid to water, not water to acid and wear an organic vapor/acid respirator.
Choosing an epoxy garage floor coating
The final critical decision is what type of garage floor epoxy paints to use. Epoxy floor paints are tough resins that come in two separate parts that you mix together just before you apply them. You can divide them roughly into three types: 100 percent solids, solvent based and water based.
The 100 percent solid type is almost pure epoxy; it doesn’t contain solvents that evaporate. These products are expensive and difficult to handle because they harden so rapidly. They’re best left to the pros.
The solvent-based epoxies typically contain from 40 to 60 percent solids (epoxy). They penetrate and adhere well and are the choice of most pros. And they’re often available in a wide range of colors, which is one reason we chose this type for our demonstration. But they do have some drawbacks. The solvents are powerful and potentially hazardous; you MUST use a respirator (a 3M 5000 series respirator with an organic vapor/acid gas filter, or the equivalent in another brand). The respirator must fit tightly to your face so you don’t breathe the fumes. In addition, you must ventilate the garage well and keep other people away from the odors.
Epoxy paint for concrete
Solvent-based epoxy floor coating also may be harder to find. Some paint specialty stores may carry them (Sherwin- Williams and ICI Dulux, among others), but otherwise you’ll have to go to an industrial supply–type store. Check the Yellow Pages under “Paint, Wholesale & Manufacturers” or “Industrial Equipment & Supplies,” or look online.
The water-based epoxies also have two parts that you mix just before application. And they also typically contain 40 to 60 percent solids. The benefit of this type of epoxy floor coating is that there are no hazardous solvent fumes. And at least one brand, Rust-Oleum’s EpoxyShield Garage Floor Coating, is widely available at home centers.
Whether you’re working with solvent- or water-based epoxy, we recommend that you apply two coats to get enough build for long-term wear and durability. “Build” refers to the thickness of the dried epoxy film. Typically, an epoxy with a higher solid content will give a higher build. And, in general, prices tend to reflect the amount of epoxy in the mix—the more epoxy, the higher the build and the higher the price.
For a two-car garage (450 sq. ft.), you’ll need 2 to 3 gallons per coat (depending on the percent of solids in the epoxy you buy—read the container). Check the cans for coverage to make sure you buy enough.
Wear appropriate gloves, eye and lung protection, and rubber boots, according to the product labels. Turn off gas to the water heater or any other appliance located in the garage. And take precautions to keep children and pets away from the garage and driveway.
Patch the cracks
First thing in the morning, after the floor has dried overnight, fill 1/4-in. cracks and larger, plus holes or spalled areas, with an epoxy crack filler, available at home centers. Use a plastic putty knife to scrape the surface level and smooth. Let this dry for four hours (check label directions) before you begin garage floor painting your first coat of epoxy.
Mix the epoxy
Mix the two epoxy components for five minutes using a drill and stirring bit. Then pour the entire contents into a second bucket and repeat the power mix to ensure complete blending of the entire mixture.
Mix the correct amount of epoxy to cover the square footage of your garage floor according to label directions. It’s critical that you allow the mixed product to stand undisturbed for the specified time on the label before applying it. You also must apply the entire batch you mixed up before the specified time expires. We used a 40 percent solid, solvent-based epoxy from a local industrial supplier/manufacturer that had to sit for 30 minutes, and the batch had to be used up within 24 hours (and it was offered in almost 20 colors).
How To Paint a Garage Floor: Brush on Epoxy Paint Around the Perimeter
Tape the area directly underneath the garage door with duct or masking tape, then brush a 4-in. strip of epoxy along the walls and against the tape.
While waiting for the crack filler to cure, use a high-quality natural-bristle paint brush and cut in the floor edges. Also, tape the area directly underneath the garage door with masking or duct tape, allowing you to shut the door overnight. This is intended to keep out dust, dirt, pets and children until the floor is dry. And put a “Do Not Enter” sign along with tape across the doorway leading to the garage from the house.
Load the roller with garage floor epoxy
Dip a 9-in. wide, 3/16-in. short-nap epoxy roller into the bucket so only the bottom half of the roller is covered with garage floor paint. (This helps keep epoxy out of the roller.)
Roll on the epoxy concrete floor paint
Paint a big wet “W” pattern that’s about 3 to 4 ft. square, then backroll to fill in the pattern—all in 60 seconds. Finish by going over it lightly to remove roller marks.
Coating the floor
If you move at a steady pace, you should finish your two-car garage floor epoxy in less than one hour. (Remember not to paint yourself into a corner!) The solvent odors are powerful. Be sure to wear a respirator and keep the garage door open at least an hour after coating.
Keep a clean cotton rag handy and some Xylol epoxy thinner (for solvent-based epoxy) to clean up epoxy drips and spills.
Add non-skid granules
Let the first epoxy floor coating dry according to label directions. For the second epoxy floor coating, repeat Steps 7 – 9. Here’s how to paint garage floors so they aren’t glossy and slippery when wet. Add a non-skid floor coating additive into the epoxy and stir well to disperse the granules evenly.
Let the first coat of your garage floor epoxy dry overnight, for a minimum of 16 hours (or according to label directions, since epoxy products vary). Add a non-skid product to the epoxy for the second coat, especially if your vehicles drag snow and moisture into the garage, or you’d feel safer on a less slippery floor. Repeat the “cutting in” and garage floor painting like the day before.
Wait another 16 hours (check label directions) after finishing your garage floor epoxy before allowing foot traffic. You can start parking your cars on the floor after approximately three to seven days (depending on the epoxy label directions). A full cure for the improved garage floor takes approximately one month.
A coat of floor wax applied over the top of a cured garage floor epoxy will make it easier to clean.