There have been many tragic ceramic floor tile installation disasters by using the wrong membranes or none at all. If the membranes and/or bonding mortars are not compatible your bond will be lost and problems will occur.

With a floor tile installation make sure your membranes meet current ANSI standards and that manufacturers instructions are followed properly.

With floor tile installations, membranes are used for a variety of reasons, each having a specific purpose, such as moisture vapor emission membranes, cork underlay, peel and stick membranes and liquid or trowel applied membranes.

A load bearing, bonded, uncoupling membrane is also a full coverage membrane, but it's made of thicker material than the anti-fracture membrane. The air cavities that are pressed into its surface allow for lateral movement.

A cleavage membrane is not bonded to the concrete. The function of this membrane is to separate the tile assembly from the concrete and isolate the wire-reinforced mortar bed and the ceramic floor tile installation from any instability in the wood or concrete sub-floor.

A crack isolation membrane is bonded to the sub-floor to cover existing shrinkage cracks and must cover three times the width of the floor tile used, with a minimum width of 6 inches.

An anti-fracture membrane is also bonded to the sub-floor, but this membrane needs to fully cover the sub-floor in order to protect against shrinkage, moisture and expansion and/or contraction of the concrete.

With a radiant heat system a moisture barrier is important in controling moisture and stoping liquid from passing through. Always consider all of the options, because the improper use of a membrane may trap moisture and cuase condensation.

Just remember that when you're doing a ceramic floor tile installation make sure that you use the correct membrane especially if you have in-floor radiant heating otherwise you could end up with cracked tile and grout and an expensive repair bill.