Plywood Over Concrete For Underlayment

The preferred underlayment for vinyl flooring is 1 4 plywood.

Plywood over concrete for underlayment.

To install a floated subfloor system first place a layer of plywood subfloor panels with the edges parallel to the wall. Unlike other underlayment products you can use it with confidence over concrete surfaces without needing to first perform a calcium chloride test of the slab. Tap down on the plywood with a cement block to ensure all air bubbles are expelled. Nail down subfloor system get 3 4 inch minimum cd exposure 1 plywood subfloor panels 4 foot by 8 foot sheets.

Some installers will lay vinyl over existing osb or plywood subflooring if it is in excellent condition. Reviewers frequently state how simple it was to install this floor underlayment and how incredibly cushioned the floor feels. It might be done to create a subfloor for ceramic tile to be installed over an existing wood subfloor or for making a concrete countertop. Plywood is available in 4 x8 and 4 x4 sheets.

Treated plywood to the concrete with concrete screws spaced every 16 in. The reverse concrete over plywood. Nevertheless this is not all that uncommon. Lay 6 mil polyethylene sheeting over the concrete to minimize moisture migration from the concrete up into the wood flooring.

Repeat the process for all of the other pieces of plywood that need to adhere to the concrete. Once you ve installed a vapor retarder install your subfloor. It s best to place the underlayment over 3 4 inch thick plywood fastened with screws at 12 to 16 inch intervals to help decrease deflection and add stability. Installation over concrete with a calcium carbide reading of greater than 2 5 percent.

However because wood is a naturally porous substance that will absorb moisture when used as a basement subfloor these materials are often installed on mini joists known as sleepers which allow it to sit above a concrete pad. Wood panels such as plywood or oriented strand board are common subfloor choices. On projects where deflection of the plywood is a concern some manufacturers recommend applying the underlayment over two layers of 3 4 inch plywood for better rigidity. If necessary add vapor retarder before applying underlayment especially recommended if 3 4 inch wood flooring is installed over concrete.

Alternatively screw rows of treated 1x4s to the concrete 16 in. It can also be used under hardwood laminate and carpet but this is much less common these days because subflooring is typically smooth enough for these materials many of which are installed with a different type of underlayment or pad.