Plastic Liner Under Concrete Slab

Thin plastic like this is often called a vapor retarder meaning it slows the vapor down but doesn t stop it.

Plastic liner under concrete slab.

Check out our range of builders plastic products at your local bunnings warehouse. We encourage retail customers to use our click deliver or drive collect service. There are debates about this with varying national regional state and local regulations. A concrete vapor barrier is simply a sheet of polyethylene plastic visqueen placed directly on top of the sub grade before the concrete floor or slab is poured to help keep moisture from the soil from passing up through the concrete.

A much better approach is a true vapor barrier with characteristics that conform to the requirements of astm e 1745 standard specification for water vapor retarders used in contact with soil or granular fill under concrete slabs. Liquid water below the slab can diffuse through the slab as vapor then condense under the flooring which can emulsify some adhesive and destroy the floor covering. Water vapor diffusing through the concrete slab can also lead to deformation and discoloration of the floor covering material leading to costly repairs or even replacement. Covid 19 update to customers our metropolitan melbourne stores will remain open for trade customers only.

However the first piece which is anchored into the concrete with 2 1 2 inch masonry screws must be pressure treated wood as it is resting directly against the concrete slab. Build your curb at the entry of the shower stall. Polyethylene under concrete slabs. The rate that moisture escapes from a slab depends on the concrete w c the density of the finish the ambient conditions above the slab and the moisture below the slab.

Make your curb out of 2x4 s. The american concrete institute states that a vapor retarder should be placed directly under a concrete slab on grade if now or in the future a low permeable membrane floor finish will be installed upon the slab. As long as the polyethylene is protected from sunlight as it obviously is when it is installed under a concrete slab it should last indefinitely. Thanks for the question.

Monitoring and 3 year lived in experiencing compact sub base compact ab or similar 40 mil plastic liner vapor and radon.