A man installing a new window

Energy Efficient Windows

Updated January 1, 1 . AmFam Team

Your old inefficient windows could be costing you. The good news: new windows can pay for themselves in savings! Take a look at our great tips on how to save money and improve your quality of life by installing energy efficient windows.

There are many good reasons to replace those old, inefficient windows in your home. Outdated windows can waste energy and drive up your energy bills. And as these windows age, they do less to keep in the cool over the summer and retain heat during the winter.

Since the average household is paying anywhere from $1,500 to $2,500 each year in utility bills — and a full 45% of that is for heating and cooling — selecting high-performance windows can potentially save you thousands in the coming years. By upgrading to energy efficient windows, you may be able to take advantage of tax credits and other ways to keep your costs down.

Take a look at our tips on how to save money with energy efficient windows and boost your home’s quality of life in the process, too!

Tips for Buying Energy Efficient Windows

When you think home improvement, try making adjustments that result in energy savings. Old windows can be drafty, and those unpredictable drafts can wreak havoc on your utility bills. If you’re ready for new, energy efficient windows, here are a few tips to consider when making that purchase.

U-Factor. The u-factor of a window gauges the window’s insulation value or the rate at which non-solar heat flows through it. The lower the u-factor, the more energy efficient the window is. A u-factor looks at just the glass or the glazing while a National Fenestration Rating Council (NFRC) u-factor includes the frame and spacer material around the glass.

Solar heat gain coefficient (SHGH). This is the amount of solar radiation that's released as heat when it passes through a window into the home. A window with a high SHGC rating is better at using the sun to warm your home while a low SHGC is better at blocking the sun’s warmth. The window’s placement could determine which type of window goes where, so you’ll get the most energy efficient results.

Air leakage. This is pretty straight forward — it’s the amount of outside-to-inside air flow around the window. The lower the air leakage rating, the tighter the window. In some cases, a leaky window costs as much as a replacement in energy costs every two years.

Sunlight transmittance. The way a window’s glazing transmits sunlight is rated in two ways, the visible transmittance (VT) and the light-to-solar gain (LSG) coefficient. The VT is what you actually see with the human eye. A higher VT rating means you’ll see more light through the window.

The LSG is a ratio between SHCG and VT. The ratio lets you know how much light you’re seeing and how much heat is blocked. The higher the number here, the more light you see without adding more heat.

Argon filled glazing. To improve the thermal performance of windows, you’ll sometimes find that the space between the glass panes is filled with argon. Argon is an inert gas that has a higher resistance to heat flow, making it more energy efficient.

Low-emissivity window glazing. Typically, you’ll hear this referred to as low-e or a low-e coating. Adding a low-e coating to a window helps control the amount of heat coming in the window. While these windows typically cost 10-15% more, they can reduce energy loss by as much as 30-50% — making them a smart, long-term investment!

ENERGY STAR-qualified Windows Will Save You Money

Look for products that are ENERGY STAR (Opens in a new tab) labeled. These doors, windows and skylights are certified to fit certain federal standards. When replacing with ENERGY STAR certified windows, you can potentially lower household energy bills.

By consuming less energy, you be reducing your carbon footprint, too. These windows will really save you some cash at home and are earth-friendly as well.

ENERGY STAR savings for a typical home is rated according to the windows you’re replacing. Here’s what you could be saving in energy bills each year:

Save $126 to $ 465 a year when replacing single pane windows.

Save $27 to $111 a year when replacing double pane windows.

If you’d like more information how to save money on energy bills, the Department of Energy (DOE) has a very informative website on ENERGY STAR-qualified windows (Opens in a new tab) that can save you money. You’ll find in-depth information on how ratings are calculated and what different technologies are available.

DIY Tips for Energy Efficient Windows

If you’re not ready to make the investment in windows for your home yet, or you’re renting and don’t have that option, we’ve got some DIY tips to keep your windows energy efficient. By making small adjustments to keep your heating bills down, you may save big over time.

Hang curtains. One of the easiest ways to make your windows more energy efficient is by hanging thick drapes. The DOE suggests using medium-colored drapes with white, plastic backing on windows that receive direct sunlight.

Install storm windows. Storm windows can do a lot to protect your home from cold weather and winds. You can go even further by looking for low-e storm windows.

Low-e film. You can improve the energy efficiency of your windows by installing energy-efficient, low-e film to the existing glass. This is a very affordable alternative to buying new low-e glass windows.

Add caulk. Seal air leaks around your windows and window frame with caulk. This works best for stationary gaps less than a quarter inch wide.

Apply the caulk when the temperature is above 45 degrees. This means you may have to be proactive and take care of those leaky windows before the really cold weather hits.

Use weather stripping. In place of caulk, weather stripping should be used on components that move, keeping their function intact. Or better, pair weather stripping with caulk to block out air leaks and keep the chill away.

Install awnings. If too much sun is pushing your home energy bill higher, this quick DIY can help you save. Pick between permanent and retractable awnings to get the look and the coverage you want.

Regular cleaning. Whether you decide to buy new energy-efficient windows or stick with the old ones, a little regular maintenance can go a long way. Wipe down frames regularly to remove dust and dirt. Thoroughly inspect your windows every season so you can stay ahead of early cracks and leaks.

Following these tips will bring energy efficiency to your windows and keep them in top shape. To learn more about protecting your home with homeowners insurance, connect with your American Family Insurance agent (Opens in a new tab). You find the right protection for your home with their expert knowledge and guidance.

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