Low Slope Systems

A category of roofs that generally include weatherproof membrane types of roof systems installed on slopes at or less than 3:12

BUR, Built-up Roof: A roof system consisting of layers of bitumen or asphalt, which serves as the waterproofing component, with plies of reinforcement fabric installed between each layer. The reinforcement material can consist of bitumen-saturated felt, coated felt, polyester felt or other fabrics. A surfacing is generally applied and can be asphalt, aggregate, emulsion, or a cap sheet.

Modified Bitumen: A roof system that incorporates bitumen that has been modified by one or more polymers such as Atactic Polypropylene (APP) or styrene butadiene styrene (SBS) which serves as the waterproofing component. If reinforcement materials are used the may consist of saturated felt, coated felt, polyester felt or other fabrics. A surfacing is generally applied and can be asphalt, aggregate, emulsion, or a cap sheet.

Spray-applied Polyurethane Foam Roof Systems: This roof system consists of the polyurethane foam roofing material being sprayed in place over a substrate.. The foam is then provided a coating to ensure the foam is protected from ultraviolet rays.

Single-Ply Roof Membranes: Roofing membranes that are applied in one layer. Single-Ply membranes can be installed with one of five types of applications: (1) Ballasted, (2) Fully Adhered, (3) Mechanically Fastened, (4) Partially-Adhered, and (5) Self-Adhered. Seams of Single-Ply Membranes can be heat welded, and adhered using seam tape or other adhesives.

Click Here To View Types of Single-Ply Membranes Commonly Used in the Western USA