Crawl space: To vent or not to vent?
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Building here in Chattanooga (CZ-4), there is possiblity of a basement due to shallow soil before bedrock. And we’re on a slope, so crawlspace it is.
I’ve been preparing myself for a conditioned crawlspace but have run across info from 475 that is making me question. If the underside of batt insulation is sealed with a product like one of their Solitex Mento products, airtight yet vapor open, would this be an alternative to sealing the entire space? Thoughts?
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Replies
YT,
First of all, can you tell us your name?
The best advice from building scientists is summarized in this article: Building an Unvented Crawl Space.
Especially in your geographical area (Tennessee), creating an unvented conditioned crawl space is by far the best approach, for the reasons explained in my article -- certainly better than insulating the crawl space ceiling.
Martin! Thank you for the response and this site, it had been a tremendous resource.
Sorry about the nickname. I'm Brian.
I have read and reread that article and it has been my baseline but I wasn't sure if the idea of an airtight and vapor open barrier on the underside of batt insulation would be a game changer or not.
Brian