What to know about ENERGY STAR® certified windows

There are several things you can check to see if a door is energy efficient. Window and door labels have information, like U-Factor and Solar Heat Gain Coefficient (SHGC). U-Factor is a measure of heat loss. It can help you know how much heat inside a home is escaping. U-Factor numbers range from 0.10 to 2.00. Lower U-Factor numbers mean less heat escapes. U-Factor is the inverse of R-Value, which measures a material’s ability to resist heat transfer through it.

You can also look for an ENERGY STAR sticker. ENERGY STAR-certified doors have met a set of criteria to earn the sticker. The NFRC verifies ratings like U-Factor and SHGC to help homeowners find energy efficient doors. Replacing old doors with ENERGY STAR-certified doors can reduce energy bills.²

¹_{Source 2023: D+R International in support of ENERGY STAR. Savings estimates are based on EnergyPlus 9.5 modeling for typical homes in 132 U.S. cities. Ranges are based on the average savings among homes in modeled cities. Actual savings will vary based on local climate conditions, utility rates, and individual home characteristics.}

²_{Savings reflect installing ENERGY STAR certified products compared to non-certified when replacing single pane windows based on the average savings among homes in modeled cities. Actual savings will vary by product type, location, method of installation, individual home characteristics, local climate and conditions, utility rates and other factors.}