Ceramic Tile Isolation Membrane On Wood Subfloor

You can either use cement backerboard or a waterproof underlayment membrane.

Ceramic tile isolation membrane on wood subfloor.

In addition they provide a stable substrate for tile installation on oily asphalt or extremely smooth surfaces for which adhesion is a problem. Uncoupling tile has been successfully installed for thousands of years by incorporating an uncoupling layer or forgiving shear interface within the tile assembly. Most tile membranes are also designed to provide waterproofing if installed according to specifications. In fact i know that some are.

For example custom building products redgard uncoupling mat has an a118 10 rating. The crack isolation membrane is critical as it protects the tile from small movements in the wood subfloor. Tcna does still show a single layer t g subfloor with an uncoupling membrane f148 but i don t know anyone in the tile. If your subfloor is plywood you will need to lay down something as plywood will expand and contract causing your tiles to crack and or pop loose.

If the tile is being installed in a bathroom consider applying an isolation membrane over your wood subfloor to further protect against expansion and contraction. You can either roll on a liquid latex membrane or use a peel and stick crack prevention mat over the entire concrete subfloor. Firstly what i consider a crack isolation membrane is one that has and a118 10 rating. If installing over an appropriate wood surface sand the wood to make it smoother and remember that the installation will work better over a subfloor at least 1 1 8 inches thick.

Available under the brand names schluter ditra or redgard uncoupling mat this product is also known as anti fracture membrane crack isolation membrane or crack suppression membrane. Uncoupling membranes aren t recommended for tiles smaller than 2 inches square and should not be used when covering old hardwood flooring due to adhesion problems. The membrane would be much easier for you to work with as it is thin lightweight and flexible and easy to cut. An uncoupling membrane disconnects tile from its concrete subfloor and prevents cracking in the slab from being transmitted upward to the tile job.

To prevent that movement from creating cracks in your grout and tile install a crack prevention membrane after the concrete subfloor is clean flat and free of cracks larger than 1 8 inch. A 3 4 inch plywood subfloor on a joist structure with 24 inch spacing needs the extra thickness of cementboard or the floor will flex and the tiles will crack. Uncoupling membranes are primarily designed for use over concrete slabs and subfloors especially ones with defects such as depressions or high moisture levels.