Air, Argon & Krypton Between Window Panes
The sealed spaces in double- and triple-pane insulated glass can contain air or an insulating gas to reduce heat transfer.
Air
A sealed air space provides insulation by slowing heat transfer between the panes.
Argon
Argon is a naturally occurring, colorless and odorless gas that is denser than air. It is the most common insulating gas used in residential windows because it can improve thermal performance at a reasonable cost.
Krypton
Krypton can provide strong insulating performance in certain glass configurations, particularly with narrower spaces between panes. It is more expensive and is therefore less common than argon.
Is Krypton Automatically Better?
No. Performance depends on the entire glass system, including pane spacing, Low-E coatings, spacer system, number of panes and window design.
Insulating gas can slowly migrate through seals over many years. A true insulated-glass seal failure is different and can allow moisture to enter between the panes.
Related Window Terms
Insulated Glass Unit • Glass Spacer • Low-E Glass • Double-Pane Glass • Triple-Pane Glass • U-Factor • SHGC • Seal Failure