Do Energy Efficient Replacement Windows Save Money?

Do Energy Efficient Replacement Windows Save Money?

If you’re on the fence about the value of energy efficient replacement windows, think again.

Not sure about the value of new windows? You might be amazed to learn just how much household energy is lost through old or outdated windows. According to, “Heat gain and heat loss through windows are responsible for 25%–30% of residential heating and cooling energy use.” In addition, claims that “replacing old windows with ENERGY STAR certified windows lowers household energy bills by an average of 12 percent nationwide.”

But the benefits extend beyond your personal savings. Investing in energy efficient replacement windows can actually help sustain our way of life. Lower energy consumption reduces greenhouse gas emissions from power plants and homes. This means that new windows are not only good for your wallet, they’re also good for the environment as a whole.

What’s Your Climate Zone?

To find just the right windows to match your needs, you first need to determine your home’s climate zone in North America. describes windows, doors, and skylights like winter coats that can protect and insulate against the elements. “But like a winter coat, you should pick the windows, doors and skylights that make the most sense for your climate. While some windows, doors and skylights are better at keeping you warm, others excel at keeping you cool.”

So, what climate zone do you live in? Do you live in a Northern, North-Central, South-Central, or Southern climate zone?  The easiest way to find out is to visit the EnergyStar climate finder tool and select your state and county.

How to shop for energy efficient replacement windows

After determining your climate zone, the next important factor when shopping for windows is becoming familiarized with energy efficient window features. Let’s touch on a few of the most common.

1. Quality Framing Materials

As a general rule, high quality framing materials will reduce heat transfer, resulting in better insulation. Better insulation means more money in your pocket from heating or cooling bills.

There are a wide variety of window frame materials available, each with their own range of performance for strength, durability, low maintenance, and insulation. There are ENERGY STAR certified windows made from these framing materials: fiberglass, vinyl, aluminum, wood, combination, and composite. The choice you make will depend on your needs, budget, and the style of your home (wood frames work well with historic homes, for example).

2. Multiple Glass Panes

If your windows consist of single panes, then you’re losing money on energy bills every year. Two panes or “double pane” with an insulating layer filled with air or gas insulate much better. This translates into deeper savings. You can also invest in windows with three or more panes for even better insulation.

Triple pane windows have more of the air or gas-filled layers, which compounds their insulating properties. Not only are triple pane windows highly energy efficient, they also have greater impact resistance and sound insulation.

3. Low-E Glass

Low-E (or “low emissivity”) refers to a window glass coating that filters sunlight to control the comfort level of your home. Specifically, low-E glass allows natural sunlight into your home while filtering out harmful UV (ultraviolet) rays. UV rays can burn your skin, damage furniture, and fade carpets and artwork in your home.

It also filters out longer wavelengths of light (infrared light) to better moderate the temperature during the day all year long. According to, low-E glass “keeps your house warmer in the winter by reflecting certain segments of the sun’s light spectrum back into the home, and cooler in the summer by reflecting particular sections outside.”

3. Gas Fills Versus Air

Wondering which insulates better between glass panes, gas or air? For energy savings, gas is the clear winner! Some energy efficient windows use argon, krypton, or other gases between the panes. These gases are non-toxic, odorless, and colorless. Plus, they form a better insulating layer than “regular” air.

Remember, you don’t have to choose all of these window features to improve the energy-efficiency of your home. Upgrading to windows that have some of these features will make a difference in your yearly heating and cooling costs. And, more importantly, they will create a more comfortable home environment for you and your family for years to come.

Do You Need New Windows? Free Infographic.

Not sure if your home needs new windows? Our helpful infographic will give you an overview of what to look for when examining your old windows, as well as some of the benefits and potential savings you can enjoy.

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