What is the ideal thickness of the dead air space in an insulated glass unit?
windfarmer
| Posted in Energy Efficiency and Durability on
I have read that thermal loops get created in the air space of an IG unit which exceed a certain thickness. These cause unwanted heat loss.
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Replies
Redstone,
The optimal thickness of the gap between the panes depends on the type of gas fill used between the panes.
If the gas is air, the optimal gap size is about 1/2 inch.
If the gas is argon, the optimal gap size is a somewhere between 1/2 inch and 5/8 inch, depending on the outdoor temperatures you are designing for.
If the gas is krypton, the optimal gap size is about 5/16 inch.
More information here: Window Performance — Part 3.