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Airtightness and mechanical ventilation

igou | Posted in PassivHaus on

What is the limit point, in terms of airtightness, that a residential retrofit needs mechanical ventilation (with heat recovery)?

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  1. GBA Editor
    Martin Holladay | | #1

    There are too many variables (and too many unresolved technical disputes) to answer your question with a simple answer. For more information on this issue, I suggest that you read the following article, as well as the comments posted below the article: Ventilation Requirements for Weatherized Homes.

    The simple answer is that you need a mechanical ventilation system if you see condensation on the interior of your windows during the winter or if your house smells stuffy.

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