JUNE 2008

Sensible metal roofing gains homeowner interest

The Environmental Protection Agency reported that $40 billion is spent annually in the United States to cool buildings. This accounts for one-sixth of all electricity generated in a year. These staggering statistics, coupled with the rising cost of heating and cooling homes, have homeowners looking for ways to save the earth and save money on energy costs.

Homeowners can expect to save up to forty percent during hot summer months with the installation of a cool metal roof.

The metal roofing industry’s products are environmentally friendly as most metal roofs contain more than 25 percent recycled content. This level of recycled content allows metal roofing to be included on listings of ‘green’ and recycled content products. In addition, metal roofing is 100 percent recyclable. Traditional roofing products, such as asphalt (if not recycled), contribute 13 billion pounds of waste to United States landfills annually. Many metal roofs can be installed over an existing roof, without tear-off and disposal.

A cool roof is often described as one that has a high solar reflectance and a high thermal emittance. The emittance of a material refers to its ability to release absorbed heat. A roof is ‘cool’ if its surface temperature is lower, and as a result, the cooling load in the building is reduced. Solar reflectance is the most important characteristic of a roof product in terms of yielding the highest energy savings during warmer months. The higher the solar reflective value, the more efficient the product is in reflecting sunlight and heat away from the building and reducing roof temperature.

A study conducted by Oak Ridge National Laboratory found that the installation of highly reflective metal roofing coatings can save homeowners up to forty percent in summer cooling costs. Special pigments for metal roofing coatings have been developed and tested that increase the solar reflectivity of the metal roof. The vent technology creates an insulation barrier that aids heating during the winter months.