5 Things You Need To Know About Window Gas Fills

Window gas fills windows installation

While the spaces between the glass in most windows are simply filled with everyday air, certain green windows come with either argon or krypton pumped into the spaces to improve their thermal efficiency. In other words, these windows are better insulators and can help better regulate building temperature and reduce energy costs. Want to learn more?

Check out these four things you should know about window gas fills.

1. How they work

Understanding how window gas fills work can help you make the best decision on your purchase. These types of windows are made with multiple panes and then pumped with either argon or krypton (although other gasses are sometimes, but rarely, used) before being sealed up.

This works to insulate your home because these gasses are thicker than normal air, making them slow to move. Argon, for example, has a thermal conductivity about 67 percent that of air. In turn, this slow movement allows for less convection than ordinary air does, reducing heat transfer across the window.

2. Difference between argon and krypton

Both argon and krypton are colorless, odorless and non-toxic. However, when deciding which type of window to go with, it’s not about closing your eyes and choosing a window.

According to EnergyStar, krypton is the better material, outperforming argon by a good 50 percent. Unfortunately, krypton is more expensive, costing nearly 200 times more than argon per unit volume. Therefore, argon fills are more common yet still effective. However, some people, like Carroll Bogard of Pella Windows, will argue that argon is best when considering all the factors. As Bogard says, “Dollar for dollar, argon gas does the best job.”

3. The pane spacing affects gas effectiveness

There’s also a difference when it comes to the window pane spacing since this impacts how well the gas works. Argon does best in 1/2-inch spaces, so you’ll usually find this gas in double or triple pane windows. Krypton works best in smaller pane spacings, so it’s often in triple or quadruple pane windows.

4. They aren’t that expensive

Now that you understand the benefits of window gas fills, you’re probably wondering about the cost and returns. It will probably cost you a fortune, right? Not so. Windows filled with argon will only run you about $30 to $40 more per window than traditional ones.

The returns can come to you in incalculable ways. Not only can you save on energy costs since the windows better insulate your home, but you’ll also see benefits coming in increased comfort, a luxury that you can’t quantify.

5. Gas leaks aren’t a huge deal

Nachi.org reports that windows may leak by as much as one percent every year. That may seem like a scary stat, as if the windows will decrease in efficiency, but that’s not the case. As long as your windows keep about 80% of their gas fill or more, their effectiveness doesn’t suffer. That means that if your gas is leaking by one percent each year, you’ll still get 20 good years out of it!

Window gas fills can be highly beneficial in insulating buildings, and they don’t have to burn a hole in your pocket. Learn more about windows and energy efficiency here.


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