Energy Star Doors – Criteria for Energy-Efficient Doors
One of the things you can do to make your home more energy efficient is to replace your door with an Energy Star door. This guide will help you learn more about the criteria that makes a door energy-efficient. This Home Depot video presents the benefits of an Energy Star qualified door:
Doors, windows and skylights that are Energy Star qualified are independently certified and tested by the National Fenestration Rating Council (NFRC), have NFRC ratings that meet the U.S. Department of Energy’s strict energy efficiency guidelines, and are manufactured by an Energy Star partner.
Doors have lower glass-to-frame ratios than windows or skylights; this holds true even for doors like sliding patio doors that are almost entirely glass. For this reason, doors provide more insulation that skylights or windows. The Energy Star Qualification Criteria for doors is based on the glazing level (amount of glass they have) and ratings that are certified by the NFRC.
The Energy Star Program defines a “door” as a swinging or sliding entry door system that is designed for and installed in a vertical wall that separates conditioned and unconditioned space in a residential building. Doors fall into three categories:
- Opaque: no glazing
- <= 1/2-lite: <=29.8% glazing based on NFRC 100-2004 or the most recent procedure available from NFRC; includes 1/4- and 1/2-lite doors
- > 1/2-lite: >29.8% glazing based on NFRC 100-2004 or the most recent procedure available from NFRC; includes 3/4-lite and fully glazed doors
The Energy Star Qualification Criteria for doors based on the Glazing Level is as follows:
- Opaque: U-Factor<=0.21; Solar Heat Gain Coefficient (SHGC) No Rating
- <=1/2-lite: U-Factor<=0.27; SHGC<=0.30
- >1/2-lite: U-Factor<=0.32; SHGC<=0.30
What does this translate to in laymen’s terms? The higher the glazing level (amount of glass), the higher the U-Factor (rate of heat transfer) and the Solar Heat Gain Coefficient. Doors without glass transmit less solar heat and provide better insulation than those with glass.
An energy-efficient door will have the following features:
- Energy efficient core materials such as wood cladding, fiberglass and steel with polyurethane foam
- Double- or triple-paned insulating glass to reduce hear flow
- Tighter fit and improved weather stripping to reduce air leakage around the edges
You will find many retailers online that sell Energy Star products. Make sure to ask whether the door you plan on purchasing qualifies for Energy Star in your climate zone. Also, look for local rebates and promotions. You may also qualify for federal tax credits by installing an Energy Star qualified product. Lastly, remember that you’ll enjoy long-term energy savings by replacing your present door with an energy-efficient door.
