The Complete Process Epoxy Garage Floor Installers Use

Installing an epoxy garage floor takes five stages. An installer grinds the slab, repairs the cracks, lays primer, applies the coating, then seals it. On a typical two-car garage that is two days of work on site. You can walk on the floor about 24 hours after the last coat, and park on it 48 to 72 hours later, so plan on most of a week from the grinder to the car.

I have been installing these floors since 2014, and what separates a floor that lasts from one that peels is almost entirely in the first stage. This is what each step involves, how long it takes, and what goes wrong when a step is rushed.

How long does the whole process take?

Two days on site for most residential garages. One day if the floor is small, four or five if the floor is part of a wider remodel.

You can see how that lands on real jobs. The table below is our own recent installs rather than industry averages:

Job	Size	Time on site	What was involved
Reiff, Clayton	200 sq ft	1 day	Failing concrete repaired, then coated
Masksumic, Oakville	500 sq ft	2 days	Clean-out, then flake system
Esselman, Fenton	700 sq ft	2 days	Prep and repairs, then flake in two phases
Randall, Ladue	400 sq ft	5 days	Drywall and paint first, then the floor

The Clayton job in that table is the clearest example of what the five stages actually change. The concrete was cracked and stained when we arrived, and you would not know it now: it was coated and finished inside a single day.

Reiff family, Clayton, 200 sq ft, one day on site. See the full case study.

Cure time is separate from install time, and it is the part you are most likely to underestimate. You walk on it first, and park on it days later. Our guide to epoxy floor curing and drying covers the waiting periods in detail.

The process, step by step

1. Grinding the slab. A diamond grinder opens the surface so the coating can key into the concrete. This is a mechanical bond, not a chemical one, which is why the diamond grinding process matters more than any product claim. Acid etching is the shortcut and it is the most common reason a floor lifts.
2. Repairing what the grinding exposes. Once the surface is open, we fill and level the cracks, pits and spalled patches. Doing this after the coating is down means doing it twice. Our surface preparation guide goes deeper into the prepping methods.
3. Primer. A primer coat soaks into the opened concrete and gives the epoxy something to hold. Skimping here is invisible on day one and obvious in year two.
4. The coating. The epoxy itself goes down in measured coats, usually one or two. The product fixes the mixing ratio and the working time, not preference, and a batch mixed wrong never cures properly however well it is spread.
5. Flake and sealant. If the floor is getting a flake or quartz finish, the flake is broadcast into the wet coat. A clear sealant then goes over the top, which is what you actually walk on and what takes the wear.

Why does the slab get a moisture test first?

Because a slab pushing moisture upward will lift a coating off however carefully the other five stages were done.

The standard check is simple. A square of clear plastic is taped down to the bare slab on all four edges and left in place. If condensation collects underneath, the concrete is still giving off moisture.

The moisture test runs before any grinding starts, and it is the one result that can stop a job on the day. If a slab fails it, I will not coat it that day, whatever is on the schedule.

What happens if you do not grind the concrete first?

The coating sits on the surface instead of bonding into it, and it comes off in sheets rather than wearing down evenly.

The failure mode is the giveaway. A properly bonded floor that has taken a beating looks worn. An unbonded floor looks like paint peeling off a wall, often lifting in large pieces that take the primer with them.

Repairing it is not a touch-up. The whole floor goes back to bare concrete before anyone reapplies anything.

How many coats go on a garage floor?

A primer, one or two coats of epoxy, and a clear sealant over the top. So three to four layers depending on the system.

A single-product, single-coat kit is not the same floor and will not last the same time. If you are still comparing systems, our guide to epoxy coating sets out the differences, and polyaspartic against epoxy covers the main choice people face.

What are the common problems with an epoxy floor?

Nearly all of them trace back to preparation or to conditions during curing rather than to the epoxy itself.

• Peeling in sheets. The slab was not ground, or it was damp.
• A soft or tacky finish. The batch was mixed off ratio, or it cured too cold.
• Cloudiness or blushing. Humidity during curing.
• Roller marks and pinholes. Applied too thin or worked too long after mixing.
• Cracks reappearing. The slab moved. A coating follows the concrete underneath it.

You do not always need a coating at all. If the slab is sound and you simply want the garage to look cleaner, a kit off the shelf will do it, and I would rather say so than sell you a system you do not need. The cases where a coating is the wrong answer entirely are covered in when not to use epoxy flooring.

What do epoxy floors look like after five years?

A well-prepared floor simply looks used. The sealant carries the wear, gloss dulls slightly in the traffic lanes, and the color underneath stays put.

Recoating is a maintenance job rather than a rebuild. The Albers garage in Weldon Spring, 800 sq ft, already had an epoxy floor the owner found flat and generic. That one was a recoat with a flake and crushed stone finish, and it took two days rather than a full teardown.

For how long a coating typically lasts before that point, see how long epoxy flooring lasts.

What the sequence looks like on a real job

The order of trades matters as much as the order of coats, and it is one of the clearest signs someone has done this before.

On the Leitner garage in Fenton, 700 sq ft in the Tapawingo neighborhood, the epoxy floor went in first and cured fully before we installed cabinetry, a workbench, Slatwall and two overhead racks. Working heavy components over an uncured floor is how a new floor gets damaged before anyone parks on it. What we found on that job was that the order decided the outcome: the floor had to be finished and fully cured before a single cabinet came through the door.

“Brandon and his crew showed up when they said they would, worked hard all day, and came back the next day to complete the job. Brandon was very timely with his communication and price quote.”

On the Randall garage in Ladue, 400 sq ft, it ran the other way round on purpose. Drywall and painting were finished first so patching dust and paint could not contaminate the fresh coating.

Where a floor is one part of a full garage remodel, that sequencing decision gets made before anyone books a date.

Frequently asked questions

Questions worth asking your installer

Watch these on video

Short clips from our own installations. Each one plays in a window on this page, so you keep your place. The link under each one opens the full written answer.

What to do next

If the slab is cracked and moving, or the concrete is spalling badly, no coating fixes that. It is a concrete repair first, and I would rather say so before the grinder comes off the truck.

Call 314-308-7780 or ask for a free in-home estimate. We look at the slab, test it for moisture, and tell you what it will hold before we quote.

Garage Designs of St. Louis has been installing garage floors from Fenton since 2002, and we have been accredited by the Better Business Bureau, or BBB, since 2008.

I am Brandon Coleman. I joined Garage Designs in 2014 installing epoxy floors, moved into full remodels in 2021, and bought the company in May 2023. We are open Monday through Friday, 8 AM to 5 PM.

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