Energy Swing Windows & Doors | Window & Door Encyclopedia | Does argon or krypton gas between panes increase energy efficiency?

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For air to insulate well, it needs to be as still as possible because moving air carries energy. Both argon and krypton are heavier than air, making them less prone to convection or thermal movement. The bottom line is that heavier-than-air gases offer measurable improvement in thermal performance. Both argon and krypton are found naturally in the air you breathe and are completely harmless. Argon is inexpensive, nontoxic, non-reactive, clear, and odorless. The optimal spacing for an argon-filled unit is the same as for air, about 1/2 inch. Krypton has better thermal performance, but is more expensive to produce. For Krypton to be useful, the space between glass panes must be thinner than normally desired, such as 1/4”. There are two ways to replace the air between the insulated glass panes with Argon. One is to drill a hole through the spacer that separates the two glass panes. A filling probe is then inserted into the hole and Argon is pushed into the glass space while air is pushed out. While this has been the practice in most of the glass industry, it does have a few negative drawbacks. First, it’s difficult to completely purge the space of air and get a reasonably high fill rate of Argon. Second, once the probe is withdrawn, the hole has to be plugged to keep the Argon inside. The plug is now a point of a potential failure which can affect the life of the insulated glass unit. Krypton filling is also done this way. Since Krypton is used primarily in triple pane units, two plugs have to be used, increasing the probability of future glass failures. There is a better way to get the Argon inside the unit. Higher quality glass manufacturers actually assemble the two pieces together in an Argon atmosphere. This provides fill rates of close to 100% while eliminating the potential for a future leak around the plug. Because Krypton is much more expensive than Argon, it is not typically incorporated into the unit using this method. 6. Does argon or krypton gas between panes increase energy efficiency? < back to list of questions about glass WINDOW GLASS