Built up roofing is made of multiple layers of different materials that are connected together and often used for flat roofs, or roofs with very minimal slopes. This style of roofing was created in the 1800s and has continued to stand the test of time. The four basic layers within built up roofing usually consist of base sheet, felts, bitumen, and a surfacing component.
Built up roofing has multiple layers making it extremely durable and able to withstand quite a bit of harsh wear and tear. Built up roofing can be painted or coated with reflective materials to make it have a cooling effect on the structure rather than absorbing heat, which is a great option for Phoenix residents. Many of the materials used in built up roofing are fire retardant and can withstand heavy hailstorms.
Built up roofing takes longer to install and the costs for installation are higher, so those looking for a quick job will be disappointed. Built up roofing only lasts 10 to 15 years and may require regular maintenance. There are potentially hazardous fumes that can be emitted into the air during the installation process. Because built up roofs have multiple layers, the material itself is extremely heavy. It can be damaged by high winds and is more susceptible to moisture damage.