Residential Windows & Doors Key Product Criteria

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

To find the Climate Zone for a specific county, consult the ENERGY STAR Climate Zone Finder.

ENERGY STAR Qualified Windows, Doors and Skylights 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.