Common roofing surfaces are made “cool” by applying coatings which are either white or contain special reflective pigments that reflect sunlight. Cool roofs protect the roof surface from ultra-violet (UV) rays and chemical damage that can cause premature aging and drying. Additionally, cool roofs absorb less heat and keep the entire building cooler and at a more consistent temperature, thereby reducing energy usage.
A standard or dark roof can reach temperatures of up to 150 degrees, but a cool roof, under the same conditions, could be more than 50 degrees cooler. Cool roofs help keep extra heat out of a building during the summer without losing heat during the winter. This means lower energy costs, and they’re also better for the environment.
Below are some examples of common roofing types and how to make them cool.
Built-up Roofs: These are the old standard tar-and-gravel combinations that are typically black or dark gray. To make them cool, replace the surface layer with a UV-resistant white mineral fiberglass surface or coating.
Roof Coatings: Roof coatings are constructed by mixing two liquid chemicals together that react and expand to form one solid piece that adheres to the roof. A reflective, protective coating can be added to offer cool-roof performance.
Metal Roofs: Metal roofs can be made cool simply by painting the surface with a reflective coating.
Modified Bitumen: Modified bitumen contains one or more layers of a plastic or rubber material with reinforcing materials, topped with a surfacing material. Add a cool-roof coating for high solar reflectance.
Shingles, Slate or Tile: For cool asphalt shingles, you’ll need specially coated granules that provide better solar reflectance. Slate and tile are available with solar-reflective surfaces in a variety of colors.
Single-ply: This prefabricated sheet is rolled onto the roof in a single layer and attached with mechanical fasteners or chemical adhesives, or held in place with gravel, stones or pavers. It can be ordered with ultra-violet-resistant and highly reflective surfaces.
Bade Roofing Company. Founded in 1954, Bade Roofing Company, Inc. is one of St. Louis, Missouri's premier family-owned and operated commercial and industrial roofing specialists. Bade Roofing installs roofing systems on major retail centers, grocery stores, hospitals, schools, warehouses and office buildings. www.baderoofing.com