High-efficiency windows: Efficient windows are essential to the passive house design. They keep much
more of the house heat inside than single-pane windows, and multi-pane windows with thermal-bridging
aluminium frames. The specific windows used vary from climate to climate, but triple-paned windows with
low-e glazing, argon gas and insulated frames are common.
The reason that multi-paned windows are important for heat and energy conservation can be visualised from this diagram ...
As you can see from the above, triple-paned windows, even without argon or other rare gases inside, retain much more of the heat of the interior air during winter than single-paned windows.
Links to pages about the seven precepts of Passive House design.
Very efficient Insulation
No thermal bridges
Passive solar gain
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