Offered as an efficient and cost-effective alternative to traditional sub-base courses Delta-MS , a dimpled sheet, is made from high-density polyethylene (HDPE), and is supplied in roll form for quick and easy laying. Resistant to acids, alkaline, oils and solvents, the material has a high compressive strength in the region of 250kN/m2. The design of the sheet ensures good pressure distribution and low point loads. It also protects the foundation slab from rising damp, and cement grout from seeping into the ground. Each sheet overlaps the next by at least 200mm for an effective seal, and specially-designed spacers ensure steel reinforcement sits above the membrane at a consistent level.