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Personal: Residential

Gas Fills

Most manufacturers offer inert gas fill in glazed units as an option to increase thermal resistance and reduce heat loss. The gas used is odourless, colourless and non-toxic. Under normal conditions it will remain inside the glazed unit for many years. Argon is the most common gas, but krypton may also be used, especially in triple-glazed products.

Argon transmits heat poorly. In addition, because it is heavier than air, any heat it does capture becomes trapped between the window glazings.

Krypton gives slightly better performance than argon. As a result, the panes of glass can be closer together. Thus, less of this expensive gas is necessary, and multiple-pane systems are less likely to experience stress breakage.