Damp Proof Membrane

Supplier: Thirty Six


A DPM (damp proof membrane) is a plastic sheet membrane that sits between a concrete slab or screed, and acts as a barrier to stop moisture and contaminants entering a property from the ground. DPM membranes are laid either under a new concrete slab or on top of it to prevent moisture transmission. Ordinarily you will have a bed of hardcore on the ground then either a blinded surface and a DPM before a layer of concrete, or you place the DPM on top of the concrete slab before the final flooring. If you suspect the groundwater to contain sulphates, then the DPM should always be placed below the concrete.