Chip board, cushioned vinyl flooring, particle boards of any type, planks and hardwood floors are unsuitable substrates to directly install ceramic tile over.
Although it can be done successfully, many experts believe that ceramic tile installed directly to plywood surfaces should be avoided whenever possible. Plywood has a smooth surface and tends to swell, warp, and delaminate when it is exposed to moisture. Install at your own risk.
To prevent moisture from damaging the plywood substrate we recommend that a waterproofing membrane be installed per the manufacturer's instructions over all plywood surfaces to be tiled.
Install ceramic tile using a latex modified thinset mortar approved for use over plywood substrates.
Installing Tile Over Vinyl Or Linoleum Floor Coverings
Installing ceramic tile directly to vinyl or linoleum surfaces should be avoided as well.
In any case, vinyl or linoleum flooring must be a non-cushioned type and securely attached to the subfloor. If the floor covering does not contain asbestos fibers we recommend that the surface be scarified or sanded to provide a rougher surface for the thinset mortar to bond to.
Install ceramic tile using a latex modified thinset mortar approved by the manufacturer for installation over vinyl and linoleum surfaces.
Installing Tile Over Ceramic Tile Backerboards
To prevent moisture from damaging the plywood subfloor we recommend that a waterproofing membrane be applied per the manufacturer's instructions over all ceramic tile backerboard surfaces installed in wet areas, including shower and tub wall facings.
Installing Tile Directly To Concrete Slabs
Paint, cutback adhesives, gypsum based fillers or levelers, sealers, or chemically treated cement substrates are unsuitable surfaces to install ceramic tile over and should be removed by non-chemical methods whenever possible.
Make sure to fill in and float off any dips, humps, or waves on the concrete foundation using a portland cement based floor leveler. For dips, this product may be used to fill the cavity and screed off using a level or straight edge. For humps, apply the floor leveler around the base of the protrusion. Then, using the top of the hump as a guide, screed the floor around the base of the hump in a circular motion. This will help to lessen the impact the protrusion will have on your finished floor.
Most cement based floor levelers need to cure for at least 24 hours before the tile can be installed.