5 Reasons Why Epoxy Floors Fail

by Dec 23, 20200 comments

5 Reasons Why Epoxy Floors Fail

When we say “Fail”, we mean that the epoxy did not last as long as intended. When properly installed, epoxy floors will last 5-10 years in an industrial environment, 10-15 years in a commercial store, and 20-30 years in a residence.

 Epoxy floors fail for one or more of the following scenarios:

  1. Floors not properly prepared to industry standards
  2. The epoxy used is a cheap epoxy or waterbased 
  3. Wrong type of Epoxy used 
  4. Moisture issues 
  5. Oils and Greasy stains

1. Floors not properly prepared to industry standards

If the concrete is fairly new, the industry standard is to “remove the cream” layer of concrete. The “cream layer” of concrete is what floats to the top when they are smoothing out new concrete. This layer is very dense and creates a slick, shiny surface (image on the left). If you spill water on it, the water will not immediately soak in. Epoxy does not stick to slick, shiny surfaces, so the cream layer must be totally removed (image on the right).

Some installation companies only scratch up the cream layer, thinking that it will be enough. WRONG. This is what leads to failure, instaling epoxy on shiny, slick surfaces.

The following is an excerpt from another article on garage floors. The steps covered in this article however, explain exactly what needs to happen for the floor to be properly prepared.


For the Preparation stage, you’ll need the following:

Tools Required:

  • Floor Grinder

  • Hand Grinder

  • Diamond Grinding Wheels

  • Orbital Sanders

  • 100 Grit Sandpaper

  • Concrete Vacuum

  • Shop Vac with HEPA filter

  • Mop and Bucket

  • Crack Filler

  • Masking Tape

In the preparation stage, you’ll need to be aware of where dust may come from during the application stage. In our project, there were no garage doors so we had to build a dust barrier. We used sheets of plastic and extension poles to keep the dust out.

You also need to plan your exit for the application stage. We had a plastic wall barrier we couldn’t easily exit, and we had 2 other doors in the garage. One of the doors lead to the back yard where there was a lot of construction debris and dust, so we locked that door. The other door lead into the house, so we chose that as our exit. This is important because, in the end, you don’t want to end up panting yourself into a corner.

Diamond Wheel Grinding

The first thing we did was diamond wheel grind the floor. We used a floor and hand grinder to accomplish this. How deep do you have to grind the concrete? The objective is to remove the “Cream” layer of concrete.

The floor grinder with diamond blades did about 95% of the main floor. You really can’t get the machine too close to the walls, or in corners. For these hard to reach places we used a hand grinder attached to concrete vacuum. With the hand grinder, we can grind the leading edge of where the epoxy will stop.


Grinding creates a lot of concrete dust which needs to be vacummed up. Vacuuming not only removes the concrete dust, but it also reveals where we missed any spots. We use a special concrete vacuum, a shop vac with HEPA filter and a regular wet/dry shop vac through out the project.

Dust Blower

We used a dust blower to blow any concrete dust that was just outside the garage doorway. All of that dust has the potential to blow back into the garage while we are in the application stage. So, the dust blower is a good option to get rid of that dust.

Crack Filling

Most concrete floors have one or more minor cracks. This is normal. The cracks have to be widened with a grinding wheel, so that the crack filler can adhere to the concrete, expand and seal the crack.

The reason why we fill the cracks is because epoxy is so liquidy, that it will go into the crack and keep going. This reduces the amount of epoxy on the surface. So, the crack filler stops the epoxy from “gravity feeding” into the crack.

Grinding The Cracks

After filling the cracks, the filler expands filling the crack, but it also makes a high spot in the floor. Now we have to go back and grind these high spots down.

More Vacuuming

After grinding the crack filler, we have to vacuum again. It is super important that all concrete dust is removed.

Mopping Up Remaining Dust

The final preparation step is to mop up any remaining dust. We use a mop, bucket and plain water to mop up the dust. As you mop the concrete now, you’ll notice how fast water absorbs into the concrete. This is because the top layer protects the concrete. Now we are going to protect the concrete with epoxy.

Cleaning The Leading Edge

We pay close attention to the leading edge of where the epoxy is going to stop, at the edge of the garage doorway. The area is cleaned by hand because we don’t want to accidentally grind over the line. As we chip off the top layer with a putty knife, we use a vacuum to grab all the particles and dust left in the leading edge of the cement.

If the leading edge isn’t cleared of the top layer of concrete, then the epoxy can chip up and fail. This happens a lot with cheap brand epoxies.

Taping The Perimeter

We laid down masking tape all around the perimeter. Basically, we put tape everywhere we don’t want the epoxy to get onto. We put it along the leading edge, and all long the bottom of the garage walls. This ensures epoxy won’t get on the garage walls.

Quickcrete Crack Filling

We used Quickcrete to fill in any remaining holes, cracks and chips in the concrete. If this isn’t done, you’ll see those blemishes through the epoxy.

Dust Barrier

Since our project didn’t have garage doors just yet, we put up a plastic wall. When it was time for the application stage, we used sheets of plastic, and extension poles to keep it in place. It worked out pretty good for keeping out dust.

If you have a garage door, now is the time to close it to keep all dust outside.

Taping The Perimeter For “Verticals”

Verticals” are any surfaces that go up and down, like a step or the concrete footing that goes around the perimeter of the garage. These areas need masking tape to protect the walls from getting epoxy on them.

See the video here.

2. The epoxy used is a cheap epoxy or waterbased

What can we say, “You get what you pay for”. You can’t skimp on epoxy flooring. Using cheap products that are latexed based with some epoxy in it, isn’t going to last at all. Latex paint, and paint for that matter belongs on walls and not on floors. Those DIY kits are really just a waste of time and money. They only last a year or 2.

 You really shouldn’t expect a waterbased epoxy poroduct to last either. Yes, some epoxies are nasty smelling, and that’s because they are solvent based. Unlike those nasty smellling brands, PurEpoxy PE-100 has no odor, and is an easy to use, 2 part epoxy.

3. Wrong type of Epoxy used

The type of epoxy to be used is determined by what the area’s traffic is like. Is it foot traffic like in a residence, or commercial store? Or is it heavy duty machinary rolling across the floor? Choose the wrong epoxy and the floor will fail, maybe not right away. But like we said, the floor wearing out faster than expected is a Fail.

4. Moisture issues

If the floor has moisture issues, meaning the slab is absorbing moisture and most likely doesn’t have a vapor barrier under it, the epoxy will defineately fail. Using a regular epoxy on a floor that has moisture issues will sooner or later create bubbling of the epoxy flooring. The issue is repairable, but will only come back again unless the entire floor is redone properly.

 Applying a product like PurEpoxy VRM Vapor Reduction would be ideal in this case.

5. Oils and Greasy stains

Oils and grease stains create a slick surface. As mentioned above, epoxy does not stick to slick or shiny surfaces. So, the oil and grease must be cleaned with a degreasing agent, and power washed off. If the plan is the grind off the cream layer with the oil and grease, that may work too.


You can easily see how the proper preparation will ensure your epoxy sticks, and holds up. Preparation is basicaly 3/5ths of the project. Do your preparation correctly , and you won’t have a failure. We also saw how choosing the correct epoxy for the area makes a difference. And basically everything needs to be moisture, oil and grease free for the epoxy to stick properly.

PurEpoxy-Hawaii has the right epoxy for your proect. At PurEpoxy-Hawaii, we trust MauiHardscapes.com to do the proper preparation work for any epoxy poroject they tackle.

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