Whether your design solution calls for a pre-manufactured Modified Bitumen membrane system, a standard built-up system, or a hybrid Built-Up Roofing/Modified Bitumen system, Firestone is uniquely positioned to meet your asphalt roofing system requirements. Firestone manufactures a diverse product line of base sheets, ply sheets, and cap sheets along with installation tools to give you a single source for quality asphalt-based roofing materials.