Ceramic Tile Subfloor Material

The subfloor is the foundation beneath finish flooring materials.

Ceramic tile subfloor material.

In basements and in homes with slab on grade foundations the subfloor may simply be a concrete slab. Perhaps more than any other flooring material ceramic and porcelain tile need a stable subfloor because any flexing or other movements will crack the tile grout and maybe even the tiles. With ceramic tile you also need to limit the deflection between joists which is a function of the subfloor thickness and how it is installed. Check for dips in the floor by sliding a 4 foot to 6 foot straight edge in different directions all around the room.

Underlayment is the material placed on top of the subfloor that assists in the installation of the tile or other type of flooring. Because of issues of moisture movement and adhesion ceramic tile will work well with certain types of subfloor underlayment systems and can go dramatically wrong with other subfloor materials. On wood frame floors the subflooring provides a continuous structural surface over the floor joists. In fact due to the problems that edge swelling creates underneath a finished floor a couple of national ceramic tile associations have discouraged the use of osb as a subfloor or underlayment.

Materials such as vinyl and carpeting are flexible enough to tolerate engineered floor truss systems with larger joist spacings such as 24 inches on center. For ceramic tile the tile council recommends using joists that are 16 inches on center a 3 4 inch thick plywood subfloor and a 1 2 inch thick cement backer board or concrete slab. For this reason ceramic and porcelain tile floors can be considered somewhat delicate despite the inherent strength of the material. This is why it s vital to evaluate the subfloor before you decide to install new tile.

It sounds like your joists are well within the acceptable limits of l 300 so your main concern is the deflection of the subfloor between joists. Cement backer board can provide a solid flat surface to install tiles on if you have a wood subfloor. Laying tile on plywood. Some form of subfloor is found beneath every type of floor whether it is hardwood carpet cermic tile natural stone vinyl or laminate and choosing the right subfloor material and installing it correctly is the key to a great floor that performs well and lasts for decades.

A plywood subfloor must be structurally sound and able to support the installation. Tile floors are heavy and tile is a hard material.