Roofing membrane is a layered material in the form of a flexible foil or non-woven fabric, used in roof constructions as protection against wind and external moisture. The roof membrane is laid directly on the sheathing or on the rafters, under the roofing, most often in sloping roof technology. Its purpose is to stop rainwater penetrating under the roofing, while allowing moisture to evaporate from inside the roof envelope. Roof membranes are vapour-permeable, thus preventing condensation in the thermal insulation layers. They come in different strength classes and can have fire-resistant or reflective properties.
The use of membranes increases durability of the roofIt improves the energy efficiency of a building and is standard in modern timber-frame construction and in the assembly of prefabricated trusses. Correct installation requires overlaps and sealing of joints with system tapes. The membrane can also act as a temporary protection against rain during the installation of the roofing.
