In civil-engineering and underground tunnel constructions, applied onto shotcrete or curtain walls – installed with the knobs to the outer shell, as a shuttering and surface drainage layer – it protects the waterproof, reinforced concrete retaining walls against seepage water and works also as lost formwork. Its high compression strength and the 20mm high knobs make possible to drain away significant quantity of water during construction and during the lifetime of the structure. It is also applicable as a ventilating sheet along not-properly waterproofed foundation- and retaining walls, installed with the knobs to the wall.
