What Is a Cool Roof?

Note: (Solar Reflectance Index is 95 for Roof Tiles Weather Proof S R I Tiles)

Cool roofs reflect and emit the suns heat instead of absorb it. By reflecting the heat of the sun instead of absorbing it, they keep buildings cooler and reduce the amount of energy needed to cool them. Coolness is measured by two properties: solar reflectance and thermal emittance. Both properties are measured from 0 to 1; the higher the value, the cooler the roof. What makes one roofing material cooler than another? When a roof can deliver high solar reflectance, and high thermal emittance, it is considered a cool roof. Reflective roofing technologies are increasingly included in federal, state and local energy codes. Many opportunities exist in both new construction and re-roofing to install cool roofs and other energy-improvement options.

Cool roofs are highly reflective and emissive materials that stay 50 to 60 degrees F cooler in the summer sun, thereby reducing energy costs, improving occupant comfort, cutting maintenance costs, increasing the life cycle of the roof, and contributing to the reduction of urban heat islands and associated smog.

A cool roof reflects and emits the sun's heat back to the sky instead of transferring it to the building below. "Coolness" is measured by two properties, solar reflectance and thermal emittance. Both properties are measured from 0 to 1 and the higher the value, the "cooler" the roof. ... A cool roof is one that will both reflect the light and UV rays from the sun while also retaining very little heat. A cool roof is highly reflective and highly emissive and will retain these physical properties for the life of its installation.

A cool roof is one that reflects the sun's heat and emits absorbed radiation back into the atmosphere. The roof literally stays cooler and reduces the amount of heat transferred to the building below, keeping the building a cooler and more constant temperature. Imagine wearing a white or a black T-shirt on a hot day. By wearing the white T-shirt you will remain cooler than if you wore a black T-shirt because it reflects more sunlight and absorbs less heat. Cool roofs like a white T-shirt, keep the internal temperature of the building cooler. The two basic characteristics that determine the 'coolness' of a roof are solar reflectance (SR) and thermal emittance

What are the Benefits of a Cool Roof?

There are numerous benefits in having a cool roof:

• Increase ecological sustainability factor, or make your house "greener" by:
• Reducing your utility bills associated with air conditioning
• Increasing occupant comfort and avoid installing an air conditioner where there isn't already one
• Decreasing the size and prolong the life of your air conditioning system
• Lowering roof maintenance costs and extend roof life, avoiding reroofing costs and reducing solid waste
• Assist your home in meeting building codes
• Assist your home in meeting building codes
• Maintain aesthetics with a roof that performs and looks good
• Receive utility rebates (in some countries)

In a nut shell, a cool roof can significantly reduce your cooling energy costs and increase your comfort level by reducing temperature fluctuations inside your home. Average energy savings range from 7%-15% of total cooling costs.

When people think about making their home more "green" or ecologically sustainable, cool roofing isn't always the first thing to come to mind. However, certain green building programs, such as the Indian Green Building Council's LEED, give credit for installing a cool roof. So if you are trying to save energy or make your home more environmentally-friendly, a cool roof is one way to achieve that goal.

How much carbon di oxide emission can be prevented by white roofs or cool roofs?

The scientist Mr. Chu calls his hero, Art Rosenfeld, a member of the California Energy Commission who has been campaigning for cool roofs since the 1980s, argues that turning all of the world's roofs "light" over the next 20 years could save the equivalent of 24 billion metric tons in carbon dioxide emissions.

About one ton carbon-di-oxide can be prevented per 100 sq ft (10x10 ft area) of white roof per year.