Can you apply epoxy over tiles

Epoxy flooring is becoming more and more popular among home and business owners. As tiles are another popular flooring option, we are often asked if epoxy coating can be applied straight on top of tiles.
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Tile removal can be a long, difficult and expensive process. Applying epoxy coating over tiles is definitely an option. However, there are a couple of factors that need to be considered before applying a durable high-performance epoxy coating.

Tiles grout lines

Grout lines are an inseparable part of any tile flooring. Due to their porous texture, grout lines tend to absorb dirt, grime, oils, and anything else that can soak into them. This can prevent the epoxy from penetrating and bonding properly.

This applies especially to kitchen flooring where cooking oils can easily be spilled onto the tile flooring. For areas like this, grout lines might have to be dug out or the entire tile flooring removed first, before applying an epoxy coating.

Adhesion of epoxy flooring over tiles

When applying epoxy over tiles, the main concern is adhesion - tiles to concrete and epoxy to tiles.
If there are any broken or loose tiles, they become a loose link in the floor. Applying epoxy over any loose links means that over time, the epoxy will peel off and you will end up with gaps in your floor. If during floor inspection or while grinding the tiles, you find any loose links, it's best for the tile floor to be removed and the epoxy applied directly onto the concrete floor.

Tiles Preparation and texture

In order for epoxy to bond property and be durable and long-lasting, it needs the right floor texture. This is why floor preparation is vital for successful epoxy flooring. The floor base needs to be porous, the pores of the floor should be open enough for the epoxy to penetrate into them. However, they should not be over or under-exposed.
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Some tiles have a glossy finish from the glazing process, which can be tricky to bond to. The glossy finish should be ground off, before applying any epoxy onto it.
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Other tiles like terracotta tiles use a glossy sealer, to prevent them from looking dirty. If a sealer is used, it will need to be ground off, as often these sealers have water repeal properties which will prevent the epoxy from bonding to the tiles.
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Vitrified tiles on the other hand are non-porous and very hard in general. Grinding these tiles alone will not be enough to prepare them for epoxy coating. If you have vitrified tiles, you will need to apply a special primer to them, before moving on to the epoxy coating.

Getting the tiles flat

Once you are happy with the condition of the tiles and you are sure the epoxy will bond to them, the next challenge is to get the tiles flat. No one really likes protruding edges or visible grout lines on their new epoxy flooring.
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Although you can apply a self-leveling compound to the tile floor, the best way is to mechanically grind the tiles. This will not only flatten the floor to the correct level, but it will also remove the top layer of the tiles and open their pores for the epoxy. Grinding the floor can also expose any loose or broken tiles.

Tile removal

Removing the existing tiles and starting on fresh clean concrete is always the best option. Removing the actual tiles is relatively easy, the difficult part lays in removing the tile's glue. If your tiles are not strong enough or not glued properly to the floor, the best thing to do is to remove them. It might cost more to remove them, but in the long run, you will have peace of mind that one day you will not wake up to a peeling epoxy due to a loose tile.