High-quality, CE-marked drainage system with an extra large water reservoir for roofs with limited fall that are planted with extensive vegetation, or where extensive drainage lengths are required. The drainage system prevents the build-up of hydrostatic pressure on the waterproofing membrane, protects it against mechanical loads and ensures that vapour is able to evaporate freely from the XPS insulation on an inverted roof. It's a 3-in-1 product (on roll) consisting of a filter geotextile and a vapour-permeable geotextile that are glued (not thermally bonded) to the dimpled core.