Ever wondered why some roofs are covered in gravel? Well, that is what you call a built-up roof.
What It Is
Built-up roofing is a traditional system that has been around since the 1840s. It is called such because it is made up of built-up layers of bitumen and reinforcing fabrics. A four-ply system, for instance, will feature a four-layer roofing membrane. Base sheets, the bottommost layer, can sometimes be mechanically attached to a roof. If a BUR is directly applied to insulation or roof decks, it is considered as being fully adhered.Read Full Article