Hi,
What floor prep do i need to do to tile on tile. Also what about expansion gaps and any pit falls you can advise on.
Hi @Markcub,
Tiling over tiles is definitely doable, but prep is everything. Because existing tiles are a non-porous surface, you’ll need to create a mechanical key first. Lightly abrade the surface with something like 120–180 grit sandpaper (or a diamond cup/grinder for larger areas) just to rough up the glaze. You’re not trying to remove the tile's surface, just scuff it so the primer can grip properly. After that, thoroughly vacuum and clean the floor so it’s completely free of dust, grease, or residue. Remember your PPE, including a P2 respirator and safety glasses.
Next, apply a suitable primer designed for non-porous substrates, such as SikaTile 015 Prep & Prime which our Special Orders team at your local store can order for you. Priming is important so don’t skip this step. Once primed and dry, you can use a quality flexible floor tile adhesive suitable for tile-over-tile applications.
As for expansion gaps, any existing movement joints in the original tiled floor must be carried through to the new tile layer directly above them. You can’t tile straight over an existing expansion joint and relocate it somewhere else, as the movement below will transfer up and crack your new tiles. Where there is an existing expansion joint, you should continue it through the new tile layout and use a flexible sealant over that joint.
A couple of other pitfalls to watch for:
If the prep is done properly and movement joints are respected, tile-over-tile can be a very successful installation.
Please let me know if you have any questions.
Mitchell
Thanks, do you sell tile over tile adhesive, i have used davco as below before around my pool, would that work.?
Hello @Markcub
Yes, the store does sell tile over tile adhesive which is the Davco 20kg SMP Evo Tile Adhesive. This will be ideal for tile over tile applications.
If you need further assistance, please let us know.
Eric
