Airtight isn’t really the best way to describe it. Rather it’s controlled air exchange, this way instead of 1000 tiny leaks all over you have a central controlled means to exchange air.
Passive home typically have ERVs or HRVs (Energy/Heat Recovery Ventilators) to achieve this, they can control the heat/humidity in the air.
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Airtight isn’t really the best way to describe it. Rather it’s controlled air exchange, this way instead of 1000 tiny leaks all over you have a central controlled means to exchange air.
Passive home typically have ERVs or HRVs (Energy/Heat Recovery Ventilators) to achieve this, they can control the heat/humidity in the air.
Has to be some kind of air exchanger
Here is a schematic I found on the Swedish version of this article: https://upload.wikimedia.org/wikipedia/commons/0/00/Passive_House_scheme_1_multilingual.svg
I suspect not all passive houses are built in this except way though.
The WSJ article has a diagram explaining the air stuff