Better roofing felts: Fid-Bau Portal

Better roofing felts

Icopal GmbH has devised a technique for making bituminous roofing membranes and joining them. The company from Werne discloses its invention in US Patent 6360506, where it reveals that the technique provides a separation and protective layer for flat or sloping wooden roofs. The invention can be laid in the same way as conventional roofing membranes. It consists of a nonwoven and this is placed over the first layer of bitumen which adheres to a carrier sheet that is sufficiently strong to withstand pulling and nailing. This may be made from glass or polyester fibre mats or fabrics. The carrier sheet has placed over it a second layer of elastomeric bitumen, which is covered by a top separation layer that may include roofing slate, nonwoven fabric or even plastic. The separation layer extends shy of the right-hand edge of the roofing membrane, but terminates at a distance in accordance with the intended overlap width. The right-hand edge of the membrane is formed by a bituminous strip which has self-sticking properties even in cold weather and this is covered by a peel-off film. In the remaining part of the overlap zone to the beginning of the top separation layer, the second layer of bitumen is covered by a plastic film that can be melted. A top section layer extends to the left-hand edge and a bitumen strip with self-sticking properties is provided at the bottom, at a distance from the left-hand edge and corresponding with the width of the overlap. A peel-off sheet exposes this layer, which covers the bitumen strip.