QA

Question: How Thick Subfloor Under Ceramic Tile

The subfloor under the tile should be at least 1 1/8″ thick, with a minimum of 5/8″ thick exterior grade plywood topped by 1/2″ cement backer board.

How thick should plywood be for a tile floor?

You’ll need to cover your floorboards with a rigid and smooth surface to prepare it for tiling. Traditionally, 12mm thick plywood was the way to go, but this can raise the floor height of the room by around 1.5cm once tiled.

Is 3/4 subfloor enough for tile?

Tile installed over wood floor systems MUST have a minimum of 1-1/4 inches of solid material beneath it. This means you can have a 3/4 inch wood subfloor covered by 1/2 inch plywood, cement board, or approved gypsum fiber underlayment.

What kind of subfloor is needed for ceramic tile?

Exterior-Grade Plywood Exterior plywood is an acceptable underlayment for tile and is preferred to interior-grade plywoods because the bonding adhesives used are waterproof. If water seeps through the tile installation to the underlayment, it will not cause the wood to swell, as happens with interior-grade plywood.

Does a plywood subfloor have to be 100% level for installing ceramic tile?

Before installing tile on your floor you must make sure your floor is properly prepared. A properly prepared floor does not have to be level.

What kind of plywood do you use under tile?

Use the Right Type of Plywood Under no conditions should you use veneer-bond plywood. Veneer plywood is interior-grade plywood that has a top and bottom layer of very thin hardwood bonded to it. Laying tile to veneer plywood risks loosening and releasing the veneer, creating an unstable base for the tile.

What kind of plywood goes under tile?

Tip: Make sure the subfloor will not deteriorate when it gets wet. Particleboard is not an acceptable subfloor material for tiling projects. Oriented strand board (OSB) and exterior-grade plywood will work if first covered with a latex-modified mortar and a tiling backer board.

How thick does the subfloor need to be for tile?

The subfloor under the tile should be at least 1 1/8″ thick, with a minimum of 5/8″ thick exterior grade plywood topped by 1/2″ cement backer board.

Can you tile 3/4 plywood?

A single sheet of 3/4″ inch plywood is normally not adequate as a substrate for tile. The tile industry recommends a subfloor that’s at least an inch-and-a-1/4 thick. Underlayment should be nailed or screwed every 8 inches in the field and every 6 inches around the perimeter.

Can you tile 1/2 plywood?

To accommodate the 1/2 inch difference in floor heights, purchase or cut a transition strip of hard wood. According to the three most prevalent manufacturers of backer board in the US, no, 1/2″ ply is not acceptable. All of them require at minimum 5/8ths plywood.

What is the best subfloor for porcelain tile?

1. Backer Board. This is the industry standard most preferred by construction pros when installing ceramic or porcelain tile. Backer board comes in four-foot-by-eight-foot and three-foot-by-five-foot rigid panels that contain a combination of cement, fiberglass, and sometimes crushed glass particles.

Can you lay tile directly on OSB?

You can lay tile over an OSB subfloor, but a membrane should be installed between the subfloor and the tiles to ensure a bond between the tile and the floor is made. Even if you are looking for a new subfloor to install, OSB is inexpensive and can work well with tile.

How level does the floor need to be for tile?

As noted in the first answer above, the surface to be tiled, in your case the floor, must be flat within 1/8” in 10′ when measured from the high points of the floor. To achieve this, be sure to use the appropriate patch or self-leveling compound (with the same manufacturer’s primer), but never thin set mortar.

How uneven can a floor be for tile?

As a general rule the floor needs to be almost perfectly flat. When the underside of the tile is uneven it’s difficult to get enough glue coverage. And the recommended glue coverage for indoor tiles is around 80%. Any less than that and the tiles become damaged very easily.

How do you level plywood before tiling?

Slide a 4- to 6- foot straight edge around the subfloor you’re prepping for tile. Go in all different directions, looking for valleys and hollows. If you find any uneven areas, they will need to be filled in with a layer of self-leveling underlayment before you move on to the next step.

What thickness plywood should I use for bathroom flooring?

Consider what the top layer of the bathroom flooring will be since some types of plywood are better suited for different flooring. For hardwood, tongue-and-groove CDX plywood rated AC with a 1/2- to 3/4-inch thickness is best. Specifically for subflooring, tongue-and-groove plywood is strong and will reduce squeaks.

Can you wall tile onto plywood?

If you are working in an interior setting in a dry area where the tile will never come into contact with water, you can install the tile directly onto the face of the plywood so long as you use the proper type of thinset.

What type of plywood is used for bathroom subfloor?

Traditionally, exterior grade plywood has been the subfloor material of choice for many bathroom flooring projects. Plywood is made by gluing alternating layers of wood veneer. CDX plywood (¾”) in particular is used often because it has a high level of resistance to moisture and humidity.

What is underlayment for tile?

An underlayment is the solid stabilizing layer directly below the tile and the tile adhesive (usually a thinset mortar). Using the wrong one can spell disaster for your tile installation. These poor tiles were installed improperly; they never stood a chance.

What type of plywood is best for subfloor?

Cheap and strong makes CDX plywood great for use as a structural panel such as a subfloor. Remember the letter grade of plywood only has to do with cosmetics and not strength. CDX plywood is just as strong as higher grades. CDX is a type of plywood that grades C, D or X.