Plastic Sheets Under Concrete

The concrete will be discolored anywhere the plastic touches it.

Plastic sheets under concrete.

A common example is polyethylene sheeting laid under a concrete slab to prevent the concrete from gaining moisture through capillary action. If you plan on using an opaque stain on your concrete after it cures this doesn t matter. 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. Dpc is a durable impermeable material such as slate felt paper metal plastic or special engineered bricks bedded into the mortar between two courses of bricks or blocks.

Finally some contractors in cold climates began installing a continuous horizontal layer of rigid foam insulation under their concrete slabs. If not tent the plastic so it doesn t come into direct contact with the concrete. During custom home construction often new homeowners ask why the builder places black plastic under the concrete slab for their home. A dpm may be used for the dpc.

Polyethylene sheeting under concrete slab under slab vapor retarders play a very important role in retarding moisture from coming up through the concrete and into the structure. Today most experts feel very strongly that engineered films designed specifically for use as vapor retarders should be used as vapor retarders. Concrete contractors learned that a layer of poly helps to keep a slab dry because it stops upward vapor diffusion from the soil. In this video part of.