Bryan Roofer Explains Energy Efficiency of Metal Roofing

Besides surging in popularity every year and great esthetics, metal roofing has many added energy efficiency benefits to offer home and business owners.   A recent trend in roofing is to apply paint or color to roof, also known as a painted metal roof or “cool roofing”.  Most commonly associated with LEED certification programs and green building design, cool metal roofing has been making mainstream traction among Bryan roofing customers because of the science behind its energy efficiency.

Energy Efficiency Criteria

The top two measures of energy efficiency for Bryan roofing are “solar reflectance” and “thermal emittance”.  Solar reflectance is the measure of how much solar energy is reflected away from the surface of the roofing materials.  This means that the higher the solar reflectance of the material, the more energy is reflected away from your home or building, reducing the heat that is transferred to the building.

Traditional roofs with an asphalt coating tend to have a solar reflectance of 10-20%, while a cool metal roof can reflect up to 70% of the energy away from the home or building.  Cool metal roofing only allows 30% of the sun’s original energy to pass to the interior of a structure.  Asphalt shingles allow up to 80% of the sun’s energy to pass to the structure in the form of heat, increasing cooling costs dramatically.

Thermal emittance is a measure that determines how easily an object releases stored heat energy.  A high level of thermal emittance means that your home will release the stored energy from the sun’s heat over the course of a day.  This means that your Bryan roof will help your home cool off much faster than traditional shingles.

Measurement Standards

In order for roofing materials like metal roofing to be categorized as energy efficient, they must meet stringent guidelines provided by the EPA’s Energy Star program.   In order to qualify for the Energy Star program, roofing materials must reduce cooling demand energy by at least 10-15%.  Additionally, the angle of the roof also provides additional requirements;

  • Low slope roofs must have an initial solar reflectance of 65% and 50% after 3 years.
  • Steep slope roofs must have an initial solar reflectance of 25% and 15% after 3 years.

The Energy Star guidelines do not stop there either.  In order for roofing materials to be qualified, manufacturers must ensure that all of the materials used in any given shingle, tile, etc., all adhere to the same level of solar efficiency.  This means that manufacturers can only offer warranty coverage on the lowest common denominator or the least energy efficient component of their materials.

If you are looking for a Bran roofing contractor or have any questions about various energy efficient roofing materials, like metal roofing, call Schulte Roofing®.