A Cool roof should be designed to reflect more sunlight than a conventional roof, absorbing less solar energy. This lowers the temperature of the building just as wearing light-colored clothing keeps you cool on a sunny day. Conventional roofs can reach temperatures of 150°F or more on a sunny summer afternoon, sun. Under the same conditions a reflective roof could stay more than 50°F (28 °C) cooler. This can save energy and money in buildings with air conditioning, or improve comfort and safety in buildings without air conditioning, by reducing heat flow from the roof into the occupied space. Most cool roofs have high “thermal emittance”—the ability to shed heat by giving off “thermal infrared” radiation. Nearly any type of building can benefit from a cool roof, but consider the climate and other factors before deciding to install one.
Benefits of Cool Roofs:
A cool roof can benefit a building and its occupants by:
- Reducing energy bills by decreasing air conditioning needs
- Helping older inefficient (or undersized) air conditioners provide enough cooling for today’s hotter summers
- Qualifying for money-saving rebates from utilities or government programs
- Making it possible to downsize new or replacement air conditioning equipment, saving money and potentially increasing cooling efficiency
- Improving indoor comfort and safety for spaces that are not air conditioned
- Decreasing roof temperature, which may extend roof service life
Cool roofs can also incur a winter heating penalty. That is, absorbing less sunlight at the roof reduces heat conduction into the building, increasing the need for mechanical heating in winter. Beyond the building itself, cool roofs can also benefit the environment, especially when many buildings in a community have them. Cool roofs can:
- Lower local outside air temperatures, thereby lessening the urban heat island effect
- Slow the formation of smog from air pollutants, which are temperature-dependent, by cooling the outside air
- Reduce peak electricity demand, which can help prevent power outages
- Decrease power plant emissions by reducing the demand for energy to cool buildings.
- Help offset global warming by reflecting more sunlight to outer space
Solar Reflectance Index(SRI) Value testing is carried out as per the following:
- Test Parameters Test Method
1. Solar Absorptance ASTM:C-1549
2. Solar Reflectance ASTM:C –1549
3. Thermal Emissivity ASTM : C1371
4. Solar Reflectance Index(SRI ) Value ASTM :E-1980
( SRI Value is obtained by Calculation of Solar Reflectance and Ther
mal Emissivity) Solar Absorptance value, Solar Reflectance value ,Thermal Emissivity value and Solar Reflectance Index (SRI) Value
with low wind ,medium wind and high wind (unit:m/s) will be incorporated with your product details and your company name in the test report.
Sample Quantity and Size : 100x 100mm – 2 Nos. per variety