Homeowners frequently encounter Energy Star ratings in marketing for house materials, but you may not believe the hype or understand what the ratings mean. Here’s a quick overview of the program and how it can help you increase savings and decrease your carbon footprint.
How do windows earn Energy Star ratings?
Energy Star is a voluntary program formed jointly by the U.S. Environmental Protection Agency (EPA) and the Department of Energy, by which products can be rated for energy efficiency. Ratings can apply to residential appliances, lighting, doors, and windows.
Under the program, qualified windows and doors must be manufactured by an Energy Star partner, independently tested and verified by the National Fenestration Rating Council (NFRC), and have NFRC ratings that meet EPA energy-efficiency guidelines.
Windows that earn Energy Star ratings have certain features, which may include:
Multiple panes, often with spacers that reduce heat transfer
Higher-quality frame materials
Special glass coating that reflects more light
Gas fills between double panes to improve insulation
What do Energy Star windows mean for homeowners?
According to the Energy Star website, homeowners can save $101-$583 annually when replacing single-pane windows with Energy Star-rated ones. These windows also save 1,006-6,205 pounds of CO2, the equivalent of between 51 and 317 gallons of gasoline.
Individual savings depend on many factors, such as the products you choose and your climate. For example, Baltimore homeowners in the North-Central Climate Zone require Energy Star windows with a U-factor of 0.28 or less. U-factor measures the amount of heat transfer a window allows.
Besides reducing energy usage and costs, these windows make a home more comfortable. The interior pane of glass stays warmer, keeping the area near the window from getting too cold. They also let in less heat during the summer.