ATAS is redefining cool with its cool metal roofing products and capabilities. Many options are available to create roofs for residential and commercial construction with customized cool components.

• The material. ATAS offers roofing in aluminum, steel, zinc and copper. Metal is as natural of a material as you can get. It offers recyclability, strength, longevity, weather resistance and more. Metal also does not outgas like petroleum-based products. As these other materials age, they give off volatile organic compounds that have been shown to be harmful.

• The coating. ATAS just rolled out new coatings in 2011, bringing more options to its customers. The cool pigment paint reflects infrared radiation, allowing the color to appear the same while keeping the material cooler. This additionally aids in reducing the urban heat island effect. The KYNAR 500® PVDF or HYLAR 5000® PVDF finishes that are used carry a 30-year limited warranty addressing fading and chalking. ATAS coated materials are non-staining and virtually maintenance free. Any surface residue is easily removed with conventional cleaning solutions or detergents. The coatings are so cool that they meet national energy standards and guidelines. Many ATAS roofing products are ENERGY STAR® qualified, and they comply with the stringent California Title 24 Energy Efficiency Standards. LEED® credits also can be acquired because the ATAS coatings meet the minimum required solar reflectance index value set by the U.S. Green Building Council. An added bonus is that metal roofs can contribute LEED points beyond what the coating contributes; for instance, adding points with solar systems.

• The solar capabilities. Standing Seam Metal Roofs are the best selection for crystalline PVs because, unlike other materials, metal offers the longest service life. When installing a crystalline system that typically is warranted for 25 years of power generation, a building owner is going to want a roofing substrate that has a greater life expectancy than that of the solar panels. Standing-seam panels also provide a natural platform for attaching crystalline systems without any roof penetrations. 

• The look. Accel has numerous roofing profiles and colors. Custom colors and natural finishes also are available. The combination of color with shingles, tiles, standing seam, and other profiles brings to life eye-catching urban, rural, historical, contemporary and modern designs.

Another cool option is called Above Sheathing Ventilation, or ASV, an air space between a roofing panel and the deck. Accel has panels that can incorporate ASV technology for many years in profiles such as Dutch Seam, Granutile and Techo Tile. The combination of product design and installation method naturally creates an air space beneath the roofing. ASV also can be created in retrofits when metal roofing is installed over the previous roof system. In addition, new commercial and residential roofing projects can include ASV by specifying an appropriate air gap.

For years ATAS witnessed the benefits of ASV with its metal roofing products, but research now proves the power of ASV. After testing, the Oak Ridge National Laboratory stated that ASV combined with a cool metal roof can reduce heat gain by up to 45 percent. ORNL showed that ASV can produce the equivalent of 0.15 solar reflectance gain, and ASV can significantly reduce roofing temperatures so attic temperatures do not exceed the peak daytime outdoor air temperature.

Other benefits include:
• Reducing peak cooling demands in the summer.
• Limiting unwanted moisture.
• Negating heating penalties associated with cool roofing in the northern climates by using the air space as extra insulation in the winter months.

Standards also back ASV. Title 24 California Building Standards Section 152 and NAHB Green Building Standard Chapter 7 state that a roof installed with an appropriate air gap is considered equivalent to the prescriptive definition of a cool roof (cool pigment on metal roof) regardles