Modified Bitumen Roofing
Modified Bitumen is a roofing membrane consisting of asphalt and plastic or rubber polymers, and is therefore widely considered an evolution of asphalt built up roofing. Modified bitumen displays the built in redundancy of asphalt built up, as well as the UV resistance and flexibility of a modified membrane. This is because the polymer mix used allows the asphalt to take on its most beneficial qualities. Like with tar and gravel roofing, modified bitumen requires a surfacing material, and the most commonly used are factory applied mineral blends, and gravel. A typical life span of modified bitumen is 15 to 40 years, depending on climate and weathering. Modified bitumen is generally applied using a heat application process that melts the seams together to create a seal, yet sometimes a cold adhesive application system is used.