Making sure our windows are efficient makes sense—windows account for 10 to 25 percent of our heating bills because of leaked conditioned air. If you aren’t quite ready for the expense and hassle of installing new, energy-efficient windows, check out our easy ways to winterize existing windows and keep your home—and your pocketbook—comfortable.
Back to Basics
Check the perimeter. This may seem obvious, but even small cracks or other structural imperfections let hot air pour out of your home. Take a good look at your windows. Are there any easy-to-spot problems such as cracked glass, rotting wood, or obvious air or water leakage? If so, address those issues either as a DIY project or by calling a professional.
Seal it up. Now that your windows are sound, focus on caulking and weather-stripping. Use caulk for stationary cracks, gaps or joints less than 1⁄4-inch wide. Use weather-stripping for components that move. For links to step-by-step instructions for these easy projects see How to Weatherstrip Double Hung Windows and How to Seal Air Leaks with Caulk.
Beautiful & Functional
Showy shades. Simple window shades can be an effective way to save energy. Mount them as close to window glass as possible, leaving the sides of the shade close to the wall to help seal in air. You can try dual shades (reflective on one side and heat-absorbing on the other), quilted roller shades, or Roman shades with layers of fiber batting and sealed edges. Raise south-facing shades during a winter day, and lower them as sunlight starts to fade in the late afternoon or early evening.
The deal on drapes. The ability of window draperies (or drapes) to reduce heat loss depends on the fabric to a large extent. In general, look for thermal drapes to keep your home warmer. Hang drapes as close to the window as possible. To reduce heat loss by up to 25 percent, try hanging the drapes at the ceiling, sealing drapes at both sides with Velcro strips or magnetic tape and overlapping them in the center. You can insulate more by layering two drapes on top of each other: One inside next to the window, and the second open to the room. Close all drapes on a winter night, and keep drapes closed on windows that don’t get sun during the day.
Batten Down the Hatches
Consider storm windows. Installing storm windows is less expensive than replacing old windows in your home, and they can reduce heat loss through windows by 25 to 50 percent. They are available for most windows and come in many types, ranging from inexpensive plastic films to glass coverings treated with low-emissivity (low-e) coatings.
Money in the bank. Low-e coatings are designed to control heat transfer, keeping heat indoors—right where you want it. Check with your local utility company about incentives for low-e storm windows, and visit energy.gov/savings to find out about available tax credits, rebates or savings. Low-e coatings are usually added during the manufacturing process, but you can purchase films and add them to your current windows.
Window Shopping Tips
Ready to replace your windows? Use these tips from the Department of Energy to find the most efficient and affordable options.
• Check in with your local utility company about rebates or other incentives for window replacement.
• Choose windows with at least two panes of glass and a low-emissivity (low-e) coating.
• Choose a low U-factor for better insulation in cold climates and a low solar heat gain coefficient (SHGC) to reduce heat gain in warm climates.
• Look for the ENERGY STAR label.
• Look for more-accurate whole-unit U-factors and SHGCs, rather than center-of-glass (COG) U-factors and SHGCs.
• Have windows professionally installed according to manufacturer’s instructions to preserve your warranty.
Discover more information about saving energy at energy.gov.