What should I use to attach Ceramic Tile to Plywood? - I’m looking for advice on adhesives for mounting ceramic tiles onto a plywood backing. Finished product will be 3’x3’ interior wall-mounted murals with tiles up to 1” thick. Weight will be about 8lbs/square foot. On smaller, lighter murals I’ve used various silicon adhesives (Liquid Nails) and pre-mixed tile adhesives. I can’t tell any difference, other than price.
We normally don’t recommend to bonding to exterior glued plywood (EGP), but it can be done in interior dry applications. Plywood will expand and deform if subjected to moisture or humidity. There are thin-set dry set mortars design specifically for adhering ceramic tile to plywood that is designated as an ANSI A118.11 thin-set mortar. The silicone or urethane adhesives should work too, but the thin-set mortars are easier to work with and easier to get full adhesive contact between the tile and its substrate. I would recommend gluing and screwing a ¼” thick Hardiebacker cementitious board to the plywood and then adhering the ceramic tile with a thin-set dry set mortar that meets ANSI A118.4 or ANSI A118.15.