I applied an epoxy coating to my garage floor several months ago, and it’s already peeling! I followed the package instructions carefully – what happened?

If your garage floor is peeling so soon after application, the concrete slab must not have bonded well with the epoxy coating. Even if you followed package instructions to the letter, there could still be problems caused by:

• Dirt, Grease or Oil: The acid etching solution that’s applied before the coating doesn’t remove soaked-in oil or grease, so any stains or deposits must be completely removed before you begin. You also need to remove all traces of the degreaser you use. If the concrete is badly stained with oil or grease, you may never be able to remove enough for an epoxy coating to bond properly.
• Cleaning Residue: Throughout the preparation and cleaning process, each of the chemicals used need to be completely removed from the surface. Don’t allow the acid wash – or any other cleaning materials – to dry on the surface.


Peeling garage floor.

• Treated or Sealed Concrete: Sealants, curing agents, concrete hardeners, and other treatments to the concrete will interfere with the bonding of the epoxy. Any previous coatings should be ground off using a diamond grinder. To test, pour water over the bare concrete. If it beads up or doesn’t soak in, the concrete has a coating of sealant that needs to be removed, or it may be heavily contaminated with grease.
• Hydrostatic Pressure: If moisture wicks too quickly through your concrete, the epoxy will flake off. To test this, tape a 2’ by 2’ piece of plastic onto the bare concrete floor, and leave it for 24 hours. If moisture collects on the bottom of the plastic, your floors likely have too much hydrostatic pressure or lack a vapor barrier under the concrete for an epoxy coating to work.
• Uncured Concrete: Newly poured concrete needs to cure for about a month before applying any coating to it.
• Concrete Too Smooth: The concrete floor needs to be slightly roughened to allow the coating to stick.
• Prior Coating Failed: If a previous coating on the floor flaked or peeled, chances are that unless you figure out why, the new epoxy coating won’t stick either.
• Bad Material: DIY epoxy kits have mixed reviews, with the one-part kits failing more frequently than kits which require mixing two parts together. Make sure to buy a product that has received positive reviews and has a high success rate.

Further Information

• How to Seal a Garage Floor (Video)
• Applying Epoxy Coating to a Garage Floor (video)
• How to Deal with Condensation on a Garage Floor (article)

Tags: , concrete, garage, how to paint garage floor, paint, Painting