There are two materials commonly used for laying ceramic on plywood or osb that are applied before the tile.
How to install ceramic tile over plywood subfloor.
It should be fastened to the subfloor using thinset and then screwed down every 10 square.
When applying cement backer board over a plywood subfloor be sure to adhere the two surfaces together with thin set adhesive.
The plywood adds stiffness and stability to the floor.
Use thinset with a higher latex content thinset is the wet base that you first trowel on the plywood to make the tile stick.
This is a mixture of cement fine grain sand and water that will adhere the new tile to the old.
Apply the crack suppression membrane over the joints of the boards.
Lay down a vapour barrier overtop the concrete pad then fasten 3 4 inch plywood using a ramset to the concrete pad through the vapor barrier then install the heating system to the plywood followed by applying the self leveling mortar over top the heating system and plywood and finally installing the tiles over top that.
It s usually a good idea to vacuum the floor just prior to spreading the thinset for the tiles.
If you find hollows and valleys you must fill them with a self leveling underlayment.
A successful tile installation project requires a level surface.
And screw the cement backer board down with special screws that countersink into the backer board such as backer on screws available at the home depot.
When it comes to mortar latex or epoxy options are best for installing tile over tile.
Add a layer of 1 2 in.
This will distributed the stress caused by movement of the subfloor and prevent cracking in your tile.
When the tile installer enters the room and is ready to begin working the subfloor must be completely flat and clean and all mortar used to install the underlayment must be dry.
You will use the flat trowel to apply a thin layer according to the manufacturers specifications.
Also consider that doors cabinets and other hardware might need to be reworked or replaced with new ones to compensate for the higher floor.
Fill seams in the subfloor with caulk.
6 18 width across the joint.
Bc plywood over the old subfloor using construction adhesive and driving 1 1 4 in.
Concrete board concrete board also called backer board comes in 1 4 and 1 2 thicknesses and is usually sold in 4 x 6 sheets.
Check for dips in the floor by sliding a 4 foot to 6 foot straight edge in different directions all around the room.
While tile can be laid on plywood do not install tile directly onto the plywood subfloor itself.
With the plywood in place install the backer board as you normally would.