One of the most frequently asked questions consumers have when purchasing a new window for their home is whether or not Argon gas filling is worth the cost in insulating glass units. Argon gas is added to the spacer within the glass unit and designed to increase insulation.

Depending on the size and type of insulating glass unit being provided, the Argon “upcharge” can seem substantial. Additionally, there have been numerous claims about the effectiveness of Argon gas. Sometimes, it’s just hard to know what to believe. To clear up the confusion and help you make an intelligent decision, let’s start from the beginning.

What is Argon Gas?

Argon is an inert gas found in the atmosphere, meaning we breathe some amount of it every day. It is non-toxic and is regularly used as a filler agent in pressurized containers and welding gas mixtures. It is odorless, tasteless, and colorless. Several inert gasses have been found to be good insulators.

Why is Argon Gas Used in Windows?

Adding Argon gas to the air mixture within an insulating glass unit’s spacer cavity achieves a lower “U-Value” and thus a higher insulating value. Lower “U-Values” indicate better thermal performance – less heat transfer through the unit. Argon makes the insulating glass unit more effective from an energy performance standpoint. Wouldn’t all insulating glass units benefit from the addition of Argon gas? Yes, but some factors need additional consideration. Depending on the type and configuration of the insulating glass units being used on a new home, Argon gas may be required to help comply with building and energy codes in certain parts of the country.

The Argon Gas Debate

The basis of the “Argon debate” centers around two questions. First, is it worth the cost? Essentially, over time, will the savings provided by Argon exceed the price? Secondly, how do you know that you received the Argon they paid for if it can’t be seen, smelled, or in any other way recognized? Both of these questions have been asked since Argon made its entry into the insulating glass production domain. Both questions are reasonable to ask. As with many things in life, the answers are a little more complicated than the questions.

Argon Gas Cost for Insulating Windows

The cost-benefit calculation is not an easy one to perform. There are numerous factors at play including:

• The size of the windows being analyzed.
• The glass composition used.
• The location (geographically) of the building.
• The orientation/direction of the building’s windows.
• The final cost of the Argon upgrade.
• The planned life-cycle of the building (or at least the intended duration of the occupant who paid for the Argon upcharge).

The window system treatment needs to be taken into account within the context of the entire building’s energy design. It would seem not smart financially to spend money upgrading the windows in a new building while not correctly providing for efficient roof and wall insulation. An engineer or architect may be required to nail down the correct answer to the cost-benefit question positively. Remembered that the supplier of the windows benefits financially by selling the consumer a higher-priced product, so there is always a possibility that the Argon product’s performance capabilities will be “over-sold” by the supplier. With this in mind, let’s now move to the other question to be addressed. Specifically, how does a consumer even know if they got Argon in their unit in the first place?

Argon Gas Detection

When Argon first made its way into the insulating glass manufacturing industry, there were several fraud cases regarding its use. Specifically, certain manufacturers were cited for selling insulating glass units as having been Argon-filled when, in fact, they had not been. As previously stated, Argon is odorless, tasteless, and colorless. It’s tough to detect, and the typical consumer would have no way of knowing if the Argon was in the units sold to them or not. Some studies performed indicated that while Argon had been put into a unit initially, most of it had escaped (leaked out of) the unit within just a matter of months after manufacturing. While there was never doubt that Argon worked to improve thermal efficiency, there were legitimate concerns and doubts about what the consumer might be getting for their money when Argon was involved.

Today, Argon’s testing has dramatically improved. The larger, legitimate suppliers of insulating glass units are trustworthy and do an excellent job providing high-quality units to the public. As with most situations of this type, however, the damage done early on still affects its reputation. Other gases are now being used either with or in place of Argon. However, Argon is the most prevalent gas additive used in the insulating glass manufacturing business presently.

With all of this in mind, what should you do? First, they should research potential manufacturers to confirm that they are dealing with reputable sources. Secondly, it may make sense, especially if many windows are involved, to get professional help in the decision-making process. Be patient. Take your time and consider multiple options or approaches. While each situation is unique, a careful evaluation should yield the right answer—it almost always does.