Humidity equalization?
Ytsehoos
| Posted in Mechanicals on
I’m finishing up a sealed crawlspace/basement area over a new build. There is some airflow between the crawlspace and house. If I install a dehumidifier in the crawlspace, will it dehumidify the house (over time) or will the crawlspace be dry and upstairs remain humid?
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Replies
It depends on the flow rates and moisture sources.
Hey Brian,
In a sealed crawlspace you should have airflow between the crawlspace and the living space above. This is typically provided by floor registers. This way, the crawlspace air and the conditioned air are one-in-the-same. According to Martin's article on this subject, you may need to run a dehumidifier in the crawlspace for a few months to remove construction moisture, but it shouldn't take long for the relative humidity in the house and crawlspace to stabilize. Then you shouldn't need the dehumidifier. Here the article I am referencing:
https://www.greenbuildingadvisor.com/article/building-an-unvented-crawl-space