ASTM Standards for Measuring Solar Reflectance and Infrared Emittance of Construction Materials and Comparing their Steady-State Surface Temperatures
نویسندگان
چکیده
Numerous experiments on individual buildings in California and Florida show that painting roofs white reduces air conditioning load up to 50%, depending on the thermal resistance or amount of insulation under the roof. The savings, of course, are strong functions of the thermal integrity of a building and climate. In earlier work, we have estimated the national energy savings potential from reflective roofs and paved surfaces. Achieving this potential, however, is conditional on receiving the necessary Federal, states, and electric utilities support to develop materials with high solar reflectance and design effective implementation programs. An important step in initiating an effective program in this area is to work with the American Society for Testing & Materials (ASTM) and the industry to create test procedures, ratings, and labeling for building and paving materials. A subcommittee of ASTM E06, E06.42, on Cool Construction Materials, was formed as the vehicle to develop standard practices for measuring, rating, and labeling cool construction materials.
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Solar Reflectance and Thermal Emittance
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