TL;DR
Argon gas fill is the replacement of plain air between insulated glass panes with argon, an inert gas about 34 percent less conductive than air, to slow heat transfer through the unit. Paired with a low-E coating it typically improves a double-pane window's U-factor by 0.02 to 0.03, a cheap gain that most ENERGY STAR windows include by default.
What it means
Argon gas fill is the replacement of plain air between insulated glass panes with argon, an inert gas about 34 percent less conductive than air, to slow heat transfer through the unit. Paired with a low-E coating it typically improves a double-pane window's U-factor by 0.02 to 0.03, a cheap gain that most ENERGY STAR windows include by default. The gas is invisible and leaks out slowly, on the order of 1 percent per year in a well-made seal. Krypton is the denser, costlier upgrade used in thin triple-pane cavities.
Where it sits in the glossary
Argon gas fill is part of the Trade jargon group inside the ProFix Directory glossary. Browse every term in this category from the glossary index.
Why Ohio homeowners should know it
This is a term Ohio homeowners encounter when reading contractor quotes, hiring paperwork, or inspection reports. Understanding it well enough to ask one good follow-up question is usually all the protection a homeowner needs.
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