3 4 Inch Plywood For Tile Floor Substrate

Tile installed over wood floor systems must have a minimum of 1 1 4 inches of solid material beneath it.

3 4 inch plywood for tile floor substrate.

I built a home about 7 years ago that is having all kinds of problems with the tile flooring cracked tile displaced grout creaky flooring 1 2 deflection in some areas. For many years the standard option was lauan plywood also called philippine mahogany or luan plywood which is made with an inexpensive tropical hardwood and therein lies its problem. We are thinking about having the 3 8th inch plywood torn out and replaced by 1 4 inch concrete board before the new tiles are installed. It typically comes in 4 x 8 foot sheets.

Most prefer a minimum thickness of at least 1 1 4 inch such a inch t g subfloor with inch plywood underlayment. The bare minimum recommended by most tile setters is a total subfloor thickness of 1 1 8 inch. The floor tiles became loose cracked and ugly looking over about 2 decades of use. You can use it as a stand alone product as well as a finish type plywood if it has a laminate finish that you can paint or finish according to personal preference.

Now the entire flooring of ceramic tiles needs to be torn out and replaced. Backer board panels typically measure 3 feet by 5 feet and can be trimmed as needed. This means you can have a 3 4 inch wood subfloor covered by 1 2 inch plywood cement board or approved gypsum fiber underlayment. Most plywood underlayment is about 1 4 inch thick and has square edges and a smooth knot free top face.

Cement based backer board. The average thickness of plywood sheets used for backer on counter tops is 3 4 inch. This provides adequate support for a wide range of finish materials. 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.

The builder hired used 3 4 osb for the flooring while the tile contractor used a 1 4 cbu under the tile thus achieving 1 in total depth. To cut backer board measure and mark the size you need. Leave a gap of 1 8 inch between sheets for thin set mortar or tile. Now largely regarded as the very best underlayment for ceramic tile in any application floors walls and countertops cement based backer board goes by many names.

Use 5 8 inch thick exterior grade plywood placed with the smooth side up and the top grain perpendicular to the floor framing. 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. Use 16d common nails to create a gap of 1 8 inch between the sheets. It is generically called cement board or backer board or it can also be referred to by one of the common brand names such as densshield hardiebacker and wonderboard.