The double-layer dimpled membrane is a water-storing drainage membrane and is regarded as an ideal solution for extensive roof greening

Advantages:

• Compared to normal dimpled membranes, the geomembrane offers a high drainage and water storage capacity and assumes the function of a protective, filter, seepage and water storage layer in green roofs
• The 8 mm dimples have a water storage capacity of approx. 3 L/m². The pressure resistance of approx. 200 kN/m² offers a high level of security, corresponding to a compressive strength of approx. 20 tonnes per m2. The 8 mm dimpled membrane also offers a high drainage capacity. The plant substrate can be applied directly as the geotextile is already integrated. This saves an additional work step
• Thanks to the perforation, the water-storing drainage membrane is permeable and can also be used for inverted roofs. This prevents a film of water from forming on the inverted roof insulation. The geotextile should be removed from walkable areas without vegetation. The base layer and the bedding material can then be applied directly on the dimpled membrane without changing the material, and then the pavement or slab covering can be laid on top of it

Installation:

• The sealed surface must thoroughly cleaned so that no damage can occur to the sealing after laying the drainage membrane
• The sealing must be root-resistant or protected by a root protection membrane
• Lay a non-woven fabric as a protective and separating layer with at least 300 g/m² on the sealing
• The geomembrane is laid horizontally with the dimples to the surface by rolling it out, with the filter-stable geotextile facing upwards
• The dimpled membranes are overlapped with four rows of dimples
• The dimpled membrane can be cut to the required length with a knife, but do not damage the sealing
• If the laid membranes have to be extended, the connecting membrane is pushed under at least 20 cm from below
• The horizontal overlaps must be shingle-like in the direction of the water flow. On rising components, the dimpled membrane should be raised at least 10 cm (4 rows of dimples)
• The dimpled membranes are laid step by step
• Then install a geotextile as a filter layer over the entire laid surface
• The plant substrate can then be applied directly