Tile Over Foam Insulation

There are several ways to install subflooring above the rigid foam.

Tile over foam insulation.

For tile i d contact the tile council of america or now it s called tile council of north america. If your basement slab lacks sub slab foam you ll have to install the insulation above the slab. I usually stick them down with ardex x7r or mapei keraquick lay the ufh slc with arditex na or mapei fibreplan then tile with x7r or keraquick subject to the type of tiles being fixed. Foam board insulation is easy to use and is a great diy way to add some insulation.

It comes in standard size 4 8 sheets and smaller sizes in many different thicknesses from 1 4 inch to 2 inches. Both require an isolation board or slip sheet. The other way you could approach it is by using a heating pad over the concrete floor with tile i d also use a isolation membrane here over it. You can use either one or two layers of plywood or osb and the subflooring can either be fastened to the concrete with long tapcon screws or it can simply float above the foam.

It s important that there is no movement under the tile. No neither ceramic tile nor wood flooring should be installed directly over rigid foam insulation. Some types of thicker foam board insulation are available but they may need to be special ordered.