The Heat Island Study by Lawrence Berkeley National Laboratory led by Professor Akbari gave us all information we need to know about why temperatures are increasing in urban areas. As cities sprawled outward, we installed black asphalt roads, black roofs, and cut down trees to make room for the roads and buildings that were being constructed. The black or darker colors absorbed heat. With fewer trees, shade was minimized and the earth was not kept as cool during the heat of the day.
Knowing the problem exists is one major benefit; correcting the problem can be tied up in red tape, governmental approvals and the like for years. Fortunately for us, many quality groups, universities, governmental agencies, companies and individuals have worked diligently toward answers that will give us concrete solutions regarding cool roofing and ways to save energy in our buildings and communities.
Energy Star was a great first step. The joint venture between the Environmental Protection Agency and the Department of Energy was implemented for such a cause of saving energy while using environmentally safe products and services. Cool roofing started with Energy Star stating that cool roofs must have a minimum initial reflectivity of 0.65 and three-year aged reflectivity of 0.50.We now had a starting point. Work performed by Lawrence Berkeley Labs and Oakridge National Labs gave us scientific support that cool roofs and cool environments can save energy.
The Cool Roof Rating Council (CRRC) has been another key organization advancing cool roofing. A membership comprised of industry leaders with experience in technical, manufacturing, testing, marketing and installation has worked closely with Energy Star and is developing programs to take cool roofing to the next level. The CRRC has established initial reflectivity measures of 0.70 and initial emittance measures of 0.75. The California Energy Commission require buildings in California that are subject to cool roof requirements of Title 24’s Building Energy Efficiency Standards be tested and rated through the CRRC and be labeled accordingly.
Now Energy Star and CRRC are currently working together on revising specifications to incorporate testing and reflective and emissive criteria. A revised specification draft was released last December. Comments on the draft were submitted until January 19, 2006. Now the EPA will review the comments and hold discussions with stakeholders. There will be a second opportunity for comments on the newer draft with a proposed effective date of Oct. 31, 2006. Only products meeting the new requirements as of this date can remain Energy Star qualified.
CRRC has plans for 2006 in continuing energy programs and cool roofing studies. One focus includes studies on high-profile steep slope roofing products such as clay and concrete tiles. The California Energy Commission has currently contracted Lawrence Berkeley National Laboratory to conduct this study. Ultimately, this will lead to a CRRC-approved method.
Research on the effects of high-profile geometries of metal roofing products on solar reflectance is being addressed and support offered by Oak Ridge National Laboratory. CRRC is working with the Cedar Shake and Shingle Bureau in the completion and verification of a method for determining the solar reflectance of steep-slope wood products such as sawn and split shakes. CRRC also has a task group to verify compound granule coated capsheet products factory manufactured roofing materials that may have different internal composition, but similar particle coating/covering, and similar radiative properties.
Energy savings and cool environments are important to all of us. Let us work together to save our natural resources, preserving their benefits for our communities, neighbors and children. Continued testing and education is crucial in developing better solutions and more options. There are so many ways we can help. Take a step forward.
