What Causes Epoxy Floor to Fail?

Epoxy floors tend to be elegant and really good-looking. But if you mess up with the application process, the results can be ugly and you might regret choosing epoxy for your garage floor. But before you hate epoxy, there are some reasons as to why they fail terribly and solutions on how to fix them. We dive deep into the reasons why epoxy floor fails and ways to avoid the problems in the future.

So what causes epoxy flooring products to fail?

  1. Surface Preparation.

The most important reason why epoxy floor fail and the one that come up frequently is when the surface is poorly prepared. If you are going to quote epoxy onto an old surface, you need to make sure that surface is ready to accept the epoxy coat. Apart from grinding the surface, you need to clean it and also dry it. Ensure that the surface is free of any dust. A lot of time has to go into preparing the surface properly to be able to coat it with epoxies.

  1. Humidity

You need to know epoxy products do not bond well with humidity, and this is mainly solvent-based your products. So when you’re recording epoxy on surfaces, you have to make sure that surface is completely dry. You don’t want any wetness any humidity.

Make sure there are no pipes or taps dripping. And, of course, make sure there’s no humidity from beneath the ground. Sometimes in areas near rivers or marshes you may actually get humidity entering and rising up to the substrate. Make sure you don’t have those problems there otherwise your epoxy coat will fail.

Also Check: 5 Best Epoxy Garage Floor Paint 2020-(Reviews and Buyer Guide)

  1. Substrate

Weak substrates may lead to epoxy floor fails. This happens when you coat the epoxy floor product onto a cement that doesn’t have the best quality. If the cement is too weak, it ends up cracking. So it’s not actually the epoxy floor that’s failing, but it’s the cement beneath that’s failing. The cement can end up breaking apart.

  1. Incorrect Primer

You must prime the surface when you’re going to apply epoxy to make sure you use a suitable primer. The primer helps seal the pores, penetrate the pores, it makes it possible for adhesion and bonding to take place. You want to make sure that this code is going to bond well with the concrete and the primer will act as the intermediate layer that will enable that bonding.  Keep in mind, floors experience heavy wear and tear. So you must make sure that you’re using a primer that will help in that respect.

  1. Conflicting Surface.

This is quite an important one. It doesn’t happen as often, but it’s quite important. What happens here is the substrate may not be compatible for epoxies. One example is you never coat epoxies on wood because wood can easily bent and can cause it to break apart. If you try putting epoxy in something that bends, the epoxy will crack because epoxy is much more firmer than the wood so it will crack.

So you want to make sure that whatever you put underneath has the same sort of tens of strength as epoxy like a strong concrete for example. You don’t want to coat on the wood. You don’t want to coat on a sheet of metal. You don’t want a coat on something that’s flexible like PVC lining.

  1. Contaminated Floors.

This problem is quite common in older installations for example an old garage, where over the years ages the floor has been polluted with various oils and greases and all types of chemicals. What happens if you try to actually call epoxy on that, you will get a reaction and there will be no bonding can take place. That’s why it’s very important to properly clean the surface.

  1. Wrong Resin.

What do we mean by this? Epoxy floors are two pack systems. They have a hardener and a resin. You need to mix the two before you actually apply the product. Now, what happens is usually these come supplied in prepackaged amounts. One mistake people make is the assume that you don’t need to weigh exactly the proportions of A component and the B component. They just think by mixing them together, they’ll be fine.

That is actually a wrong thing to do. Make sure that you are mixing the product according to the specified proportions. Also make sure that you’re mixing the product with a real electrical mixture. Some people think they can just stick a stick and mix the product. That will not work. You need an electrical mixer that’s powerful enough to create a uniform mix and a uniform mixture throughout the bucket.

What ends up happening is that your epoxy will be sticky. If it doesn’t cure properly, you may end up having a wrong proportion of the resin versus the hardware and the epoxy might be sticky, it might be soft and it will never ever cure. So make sure you don’t get that mixing wrong. Basically just follow the instructions and mix it properly.

Can epoxy be applied over the tile?

If you’re renovating an area and you want to apply epoxy over the tiles, one option you have is just remove the tiles, clean the glue with the adhesive and apply the epoxy on the substrate. You can do that but let’s face it, it is quite messy to just go through that entire procedure of stripping the tiles and cleaning up.

Can epoxy be applied over the tile? Yes, you can do it. However, this will only be possible if you ensure good bonding between the epoxy and the tiles. Tiles are notorious. They are not easy to bond with. Why? Because tiles have been coated with various chemicals to make them nice and smooth glossy.

So if you are going to coat over tiles, first thing you need to do is make sure that. You grind and sand the tiles. You want to remove the glass. You want to scratch the tiles. Scratch them so it will be possible for the epoxy primer to penetrate the tile and you can ensure good bonding.

Proper preparation.

  • So the first step is scratch the tile.
  • The next step is use a proper primer. And what I mean by that is don’t use one of those thick-sh high viscosity primers that really are like honey because those primers will never penetrate the tiles. You want to use a fluid a thin epoxy primer and use an example of a thin primer.
  • You want to use a thin primer that will penetrate the tile so you can ensure good bonding. An example of a good low viscosity primer to use on tiles is the KILZ L211101 Adhesion High-Bonding Interior Latex Primer/Sealer

How to fix the joints in tiles

So once we have arranged the bonding part, then we’ve got another issue to face. And the other fish the issue you need to face is tiles have joints. I’m assuming that if you’re going to apply epoxy over the tiles, you do not want the joints to show.

Here’s an example where you can actually see the joints of tiles showing.

How do you go about making sure that the joints won’t show? Well, the truth is you’re going to have to do some filling and grouting of the joints and that can be actually a lengthy procedure. You may actually have to do more than once.

You need to fill up the joints, smooth them out and make sure that the joints and the tiles are on the same level before you apply any topcoat otherwise the joints will show.

Do proper installation.

Another important point to keep in mind is sometimes the tiles haven’t been placed properly. Whoever installed  the tiles in the first place, if they haven’t been put in straight, the tiles might even show after you’ve evened out the joints. They still might show. This is a warning sign that you cannot be sure that all joints will be eliminated, all traces of joints will be eliminated after you have coated the floor.

So in order to get a successful epoxy floor over tiles, you may need to do several coats to make sure that there are no traces of joint showing. My recommendation is always do one thick layer to fill up the joints and then apply your final layer over the tiles.

Make sure you guarantee good bonding of the epoxy of the tiles to the epoxy. Once, you’ve guaranteed good bond, that you make sure that you filled in the joints so that the judge will not show after you have completed the coating project.


Epoxy flooring is one of the best ways to revamp and bring a new look to your old and worn out garage. IF you have all the necessary tools, you can easily epoxy your garage floor without the need of a professional installer. With so many types of Epoxies, it can be hard to decide on which one will suit your needs. But once you come up with the best epoxy flooring, all you need is to make the necessary preparations and bring a new look to your garage floor.

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