Energy Star is an international standard for energy efficient consumer products, which has its origins in the United States of America. Although originally intended as a volunteer program by the EPA, it helped promote the use of energy efficient products by labeling them with the Energy Star logo.
Today, aside from major appliances, office equipment, lighting, home electronics, etc., Energy Star is also making its presence felt in the construction industry, especially that of pre-engineered steel buildings. The roof and walls are parts of pre-engineered steel buildings that are constantly exposed to the elements, making them the largest areas that greatly affect the efficiency of these structures.
Whereas before only light colored roofs have Energy Star rating, today various roof colors, including dark ones, are Energy Star approved and therefore energy efficient.
Using cool metal roofing for pre-engineered steel buildings helps lower energy consumption significantly and aids in reducing Urban Heat Island Effect.
Pre-engineered steel buildings can be designed with any type of slope. In order for a roof color to carry the Energy Star seal, it must have a solar reflective value greater than 0.65 for low slope and greater than 0.25 for steep slope. Solar reflectivity is the fraction of the sun’s energy reflected over a surface. The higher the solar reflectivity, the less energy is needed to cool down a pre-engineered steel building.
Energy Star approved reflective roofing for pre-engineered steel buildings reflect more of the sun’s rays, lowering roof surface temperature by up to 10 degrees Fahrenheit. In addition, these roof products can help reduce the amount of air conditioning requirement of pre-engineered steel buildings. Reduction of peak cooling demand can range from 10 percent to 15 percent.