Tag Archives: built-up roofs

Commercial Roofing Industry, Manufacturers & Industry Standards

Changes in Traditional Materials For many years, traditional built-up roofs, composed of layers of roofing felts and bitumen, were the mainstay of the roofing industry. During the energy crisis of the early 1970s and recent energy concerns, the material used in built-up roofs declined in quality. During refining, more of the petroleum-based chemicals used in […]