The dimpled faced membrane FONDPLAST is applied on foundation walls to protect the waterproofing layer during the stage of back filling, as well as during any settlement of the building itself. Furthermore it will provide an excellent mechanical anti-root barrier. The FONDPLAST membrane is a high density extruded polyethylene sheet (HDPE) and can be applied both as a vertical protection or as a horizontal protection against rising damp. The product remains stable in time, does not contaminate the water to which it comes into contact and does not release any polluting substances.