Low Sloped Roofs

Single-ply Membranes are pre- fabricated sheets that are rolled onto the roof and attached with mechanical fasteners, adhered with chemical adhesives, or held in place with ballast (gravel, stones, or pavers). Some kinds of membranes, like TPO and PVC, are typically white and reflect sunlight well. Others, like EPDM, are typically black, and must be formulated differently or coated to make them reflective.

Built-Up Roofs consist of a base sheet, fabric reinforcement layers, and a protective surface layer that is traditionally dark. The surface layer can be made in a few different ways, and each has cool options. One way involves embedding mineral aggregate (gravel) in a flood coat of asphalt. By substituting reflective marble chips or gray slag for dark gravel you can make the roof cool. A second way built-up roofs are finished is with a mineral surfaced sheet. These can be made cool with reflective mineral granules or with a factory-applied coating. Another surface option involves coating the roof with a dark asphaltic emulsion. This type can be made cool by applying a cool coating directly on top of the dark emulsion.

Modified Bitumen Sheet Membranes are composed of one or more layers of plastic or rubber material with reinforcing fabrics, and are surfaced with mineral granules or with a smooth finish. A modified bitumen sheet can also be used to surface a built-up roof, and this is called a “hybrid” roof. Modified bitumen surfaces can be precoated at the factory to make them cool.

Spray Polyurethane Foam roofs are constructed by mixing two liquid chemicals together that react and expand to form one solid piece that adheres to the roof. Since foams are highly susceptible to mechanical, moisture, and UV damage, they rely on a protective coating. These coatings are traditionally reflective and offer cool roof performance.