Can You Epoxy Over Cracked Concrete?
Can you epoxy over cracked concrete? Usually, yes, as long as the cracks are repaired first. A coating does not fix a crack by itself; repair is part of the prep. Here is how installers look at cracks before coating a garage, basement, or shop floor.
Why cracks have to be repaired first
Most concrete slabs have some cracking. A coating applied straight over an open crack can show the crack through the finish, and dirt and moisture can work in at the edges. During prep, installers clean out cracks, fill them with a repair material suited to the crack, and grind the repair flush so the coating goes on a smooth, sound surface.
Types of cracks and what they usually need
What you see | What installers usually do |
|---|---|
Hairline cracks | Clean and fill during prep, then grind flush |
Wider cracks | Open up (chase) the crack, fill with a repair material, and grind flush |
Uneven cracks where one side is higher | Grind to level and repair; may point to slab movement worth checking |
Spalls and pits | Fill and level; heavy spalling may call for resurfacing |
Control joints | Clean out; may be filled or kept open depending on the slab and system |
Moving cracks are different
Some cracks keep moving as the ground or the slab shifts. A rigid coating can crack again over a crack that is still active. Signs worth mentioning to an installer include cracks that have grown, cracks with one side higher than the other, and new cracks since you moved in. These may need a structural look before any coating.
Moisture and cracks
Cracks can be a path for moisture. A moisture test before coating helps installers choose the right bonding coat and decide whether extra steps are needed.
Garage floor repair and resurfacing
When a slab has many cracks, pitting, or old patches, installers may recommend resurfacing: grinding, repairing, and leveling the whole floor before coating. A flake finish can also help hide the look of repaired cracks. See garage floor coating options and concrete coatings.
Questions to ask in your quote
Which cracks will be repaired, and with what?
Will repairs be ground flush before coating?
Are any cracks a sign of movement that needs a closer look?
Is crack repair included in the price or listed separately?
Repairs are one of the biggest price factors; our epoxy garage floor cost guide explains the rest.
Learn more
Honolulu Epoxy Floor connects you with local installers across Honolulu and Oahu. Call (808) 515-2525 or request a free quote and include photos of the cracks.
