APP 180 FR is a granule-surface APP modified bitumen roofing membrane designed to be heat-welded. It consists of select asphalt, modified with atactic polypropylene, and strengthened with a fiber glass reinforced polyester nonwoven mat [190 g/m² (3.9 lb/100 ft²)] made with 100 % recycled PET fibers. The combination results in a flexible and durable material. APP 180 FR is a membrane that is strong and stable, and resistant to natural forces and other factors on the roof-top. The addition of fire-retardant materials increases the fire resistance of the membrane. APP 180 FR is ideal for both new construction and re-roofing applications as a cap sheet or as a flashing sheet in single or multi-ply APP applications.