Torch Applied APP Bitumen Roofing
This information reflects our best understanding of product composition in 2021.
Atactic polypropylene (APP) bitumen roofing is commonly used in low-slope multi-ply roofing systems. Like styrene butadiene styrene (SBS), APP bitumen roofing is also a polymer-based asphalt with greater tensile strength, increased weatherability...
Atactic polypropylene (APP) bitumen roofing is commonly used in low-slope multi-ply roofing systems. Like styrene butadiene styrene (SBS), APP bitumen roofing is also a polymer-based asphalt with greater tensile strength, increased weatherability, and improved elasticity characteristics when compared to traditional asphalt formulations. Additionally, when combined in a membrane system, a fiberglass mat is typically added for increased puncture resistance, tear strength, and structural robustness. Within a roofing system, installation typically requires both a base and a cap sheet. This Common Product covers products that are adhered via a torching mechanism which heats the asphalt to its most effective workable ductile temperature (245 - 300°F). Products advertised as fire retardant may contain additional flame retardants beyond those captured by this CP. It is also worth noting that the mineral granules on the cap sheet allow for UV protection due to a ceramic coating that is typically applied to the granules.