Where does the humidity go in a super-sealed building?

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Where does the humidity go in a super-sealed building?

I am wondering deeply, and this question makes me doubt all wall designs.

Where does all the humidity go in a super sealed structure ?

Let's assume that a residential house has an almost perfect water vapor barrier setup
and or is very tight ( my personal example is an ICF house ), what happens to all the daily generated humidity by the occupants ??

I understand that nothing is completely vapor diffusion proofed, but if slow enough,
would the humidity level rise without stopping ?

I am asking this because of the following situation ...
I have a large ICF ( quadlock) house, on which there is a flat roof terrace,
and i have to re-build the small exit house on top of it because my carpenter helper didn't
do it properly ( all sheating got damp, some rotten wood supports etc... many many air leaks )

And i need to commit to a certain design, so i am afraid that i would actually need some excess humidity to get out, and if i go with a reflective inside insulation and or another design that would "seal" even more the vapor, there would be no way for it to get out by diffusion fast enough.

Is that worry founded ?
Do we need some walls to be somewhat permeable so we can exchange humidity levels with the outside ??

i hope i am making sense somewhat !
thanks for your time all! superb website!! :)

Asked by Jin Kazama
Posted Thu, 11/29/2012 - 23:50
Edited Fri, 11/30/2012 - 08:09