In 1999, the U.S. Environmental Protection Agency initiated a program called the Energy Star program to rate roof materials based on their energy efficiency. This initiative was intended to encourage the development of more energy efficient roofing materials to help with the cost of heating and cooling homes in America.
The hotter the roof of your home, the more energy that is required to cool it off. Likewise, the colder the roof, the more heat that is required to heat your home.
Asphalt roofing has always been the hottest roofing material on the market, but since it is the most common and the most affordable for many homes, manufacturers have developed ways to make them more efficient, motivated by the desire to earn a good Energy Star rating.
Generally speaking, darker colors absorb more heat. A dark roof will transfer more heat into the building that it protects than a light roof.
Studies have shown that buildings which have dark roofs use up to 40% more energy to cool off than buildings with reflective or light-colored roofs. On the Energy Star rating scale, lighter roofing materials have a better rating than dark ones.
Energy Star qualified shingles come in many colors, including dark brown and dark gray. They are designed with special granules in the asphalt that help them to be more reflective than standard asphalt roofing. This allows them to absorb less heat.
Qualified shingles have been shown to keep a roof as much as 100 degrees cooler than roofs without qualified shingles. This translates into 10-15% less energy being expended to cool the home during peak temperature periods.
The best way to locate the ratings for roofing materials is to check out the Cool Roof Rating Council. The council certifies for the Energy Star program and its website offers a comprehensive list of roofing materials and manufacturers. The list shows the Energy Star rating for each manufacturer and each product.
The U.S. government offers tax credit and incentives for energy-efficient home products. The incentives are updated from year to year, so a tax accountant might be your best bet to check which incentives are currently being offered.
In 2011, for example, the tax credit for installing a qualified Energy Star roof on a residence was equal to 10% of the cost of the roof up to $500.
In addition to these federal tax breaks, your state might also offer tax exemptions, grants and other incentives and credits for using eco-friendly and green building materials.