Steep-sloped roofs have a roof surface with a slope (rise to run) ratio of greater than or equal to 2:12 (9.5 degrees from the horizontal) and are often found on single family homes. The products described below are primarily on steep-sloped roofs, although in some cases they may also be used for low-sloped roofs.
Asphalt shingles are the most common type of residential roofing, as they are relatively inexpensive and simple to install. They are composed of asphalt and a reinforcement layer that is coated with mineral granules. Asphalt shingles come in two standard design options: Architectural shingles and 3-Tab shingles. Architectural shingles are generally thicker and stronger and vary in shape and size.
Tile roofing is relatively common in residential applications and is available in clay and concrete varieties. Roofing tiles are resistant to fire, hail, and moisture, and they come in a variety of architectural styles and colors.
Directionally Reflective Materials (DRM) change color depending on the angle of view. For example, DRM can appear dark from the street, but white from above. DRM products can come as a granulated product similar to modified bitumen or asphalt shingles, or in a micro stair-step pattern similar to a metal panel.
Metal roofing is commonly made of steel, aluminum, or copper. Metal roofing can come in structural metal panels or in shingle, shake, or curved facsimiles, and it is available in a variety of shapes, textures, and colors. Metal roofing is frequently coated with a factory-applied coating that provides color and durability.
Polymer or composite roofing products are manufactured from polymer to mimic natural shingles, shakes, and slate. Polymer/composite products are typically lightweight and can be fire-resistant and/or made of recycled materials.
Slate roofing is made of natural stone and is available in a variety of colors, shapes and textures.
Wood roofing products are typically manufactured from cedar wood. They are available in shake and shingle varieties.
You can search for roofing products by type on the CRRC Rated Roof Products Directory.
The standard covers test specimen preparation and test methods for measuring the initial and aged radiative properties of roofing products. The standard is referenced by building codes and rating programs worldwide in order to measure the initial and aged solar reflectance and thermal emittance of roofing products.
California’s Building Energy Efficiency Standards for Residential and Nonresidential Buildings (Title 24, Part 6) contains requirements for the thermal emittance, three-year aged reflectance, and Solar Reflectance Index (SRI) of roofing materials used in new construction and re-roofing projects.
The L.A. Green Building Code requires roofing material used in residential buildings meet minimum values for three-year aged solar reflectance and thermal emittance, or aged SRI.