Can Epoxy Be Installed Over Existing Tile Floors?

The answer to this question is a bit more complicated than a simple yes or no. Whether it makes sense to install epoxy over existing tile floors or whether the tile needs to be completely removed all depends on the condition and composition of the tile. In addition, owners and contractors need to keep in mind that just because epoxy can be applied directly over tile, it doesn’t necessarily mean it should be. Read on for more information about this complicated and sometimes controversial topic.

The Real Scoop

When epoxy applicators arrive on a job, they are often met with owners who are very wary of complete tile removal. The tile removal process can be messy, costly and add quite a bit of time to the job schedule. For these reasons, contractors often feel like the bad guys when they tell owners that a full removal is necessary.  However, contractors are only doing their due diligence after having investigated the following:

The condition of the tile. Tile can become slippery, unsanitary and unsuitable for the application of epoxy. Water, bacteria and other contaminants can reside in the mud bed on which the tile is placed. This can affect the adhesion of the tile to the substrate. If the bond between the tile and the original substrate is weakened, there will be areas of loose tiles. This, in turn, will affect the adhesion of the epoxy to the existing tile floor. If more than a few tiles are loose or otherwise compromised in a particular area, it’s probably best to remove the entire floor.

The condition of the grout lines. Because grout is porous, it can soak up grease, grime, bacteria and many other types of contaminants. And of course, if the grout lines are compromised, then epoxy will not properly adhere to the floor. During the initial inspection of the tile floors, special attention should be paid to the condition of the grout. If there are many areas where the grout is old or compromised in any way, contractors may need to not only dig up the grout lines, but also remove the entire tile floor.

The type of tile. Tile is a pretty general term, as there are many different types of tile –  ceramic, quarry, vinyl composition tile (VCT) and linoleum just to name a few. The decision to completely remove the tile or to simply mechanically prepare it for epoxy application is also based on the type of tile that was originally installed.

• Ceramic tile can found in many different areas of a building, from restrooms and locker rooms to entryways and even some offices. Ceramic tile is typically glazed and is often very slippery. With this being said, before epoxy is installed, the slick tile surface needs to be removed by either shot blasting or diamond grinding. In some instances, the surface prep process may actually compromise the tile and grout, leading to the need for extensive repair and patching. For this reason, many contractors will recommend a full removal of the tile at the outset of the job, especially if the ceramic tile is older and shows any outward signs of degradation.
• Quarry tile floors are found in places like older commercial kitchens and are often prime candidates for mechanical surface prep rather than a full tile removal. The surface of quarry tile floors is unglazed and is more “open,” allowing for shot blasting and/or grinding to properly prepare the tile surface for optimal adhesion of the epoxy.
• Vinyl composition tile (VCT) and linoleum are synthetic tiles that are glued directly to the substrate. The difference between the two is that VCT is made from synthetic materials, while linoleum is made from all natural linseed oil. In either situation, the decision about whether to remove or mechanically prepare the tile for epoxy application is based on the age of the tile floor.
  • For VCT and linoleum floors that were installed more than 20 years ago, the solvent-based mastic adhesives are often very firmly bonded to the substrate. It is often more cost effective and less labor intensive to grind the VCT or linoleum, and then apply the epoxy.
  • If the VCT or linoleum was installed more recently, it may make more sense to completely remove the tile before the installation of the epoxy for two reasons:
    • The adhesives used now days are water-based and tend to be easier to remove than solvent-based mastics.
    • Newer VCT and linoleum may still contain significant amounts of the plasticizer and/or oil ingredients used during manufacturing. This can compromise the adhesion of the epoxy to the tile.

The Bottom Line

There are many things to consider when applying epoxy over existing tile. The bottom line, however, is that you cannot put epoxy over bad tile. And even if the tile is in good enough condition that a full removal is not warranted, careful and comprehensive mechanical surface preparation is always needed.