The ENERGY STAR® criteria for residential windows, doors, and skylights are tailored to four Climate Zones. A product's energy efficiency for a given climate is based on its impact on heat gain and loss in cold weather and heat gain in warm weather. Windows that are energy efficient in North Carolina will not necessarily be energy efficient in New Hampshire and vice-versa.
Climate Zones for ENERGY STAR Qualification Criteria
The four Climate Zones for ENERGY STAR qualified windows, doors, and skylights are:
- Northern: mostly heating
- North/Central: heating and cooling
- South/Central: cooling and heating
- Southern: mostly cooling
ENERGY STAR Qualified Windows & Doors Eligibility
To be eligible for the ENERGY STAR, products must be rated, certified, and labeled for both U-Factor and Solar Heat Gain Coefficient (SHGC) in accordance with the procedures of the National Fenestration Rating Council (NFRC) at levels which meet the following ENERGY STAR qualification criteria in one or more Climate Zone. Storm windows, window films and interior doors are not eligible for ENERGY STAR at this time.
ENERGY STAR was created to help consumers easily identify products, homes, and buildings that save energy and money, and help protect the environment. As the government-backed, trusted symbol for energy efficiency, the ENERGY STAR label identifies highly efficient products and designates superior energy performance in homes and buildings.
