Crawl space in a remodel in Austin, TX (Climate Zone 2A)
I read the articles and comments on GBA site regarding crawl spaces and general preference for unvented crawl. I wonder what would be a reasonable recommendation for Austin TX? The foundation is pier and beam, and quite a few piers; laying out the vapor barrier and sealing it all may be challenging. They don’t have any mechanical equipment there. The area is generally flat-ish in the neighborhood, with 1-in-500-year flood risk. Radon levels seems low in that part of the country.
The homeowners (my family) consider spray foam for underside of the house, or a blown in fiberglass for underside. I brought up the enclosed crawl space to them, but also read https://buildingscience.com/documents/digests/bsd-111-flood-and-hurricane-resistant-buildings and see that vented crawl spaces (elevated houses) can be an advantage.
Please advise,
thanks,
Lucy
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Replies
Lucy,
I will ask a question to give your post a bump. Does the house sit on a poured or block foundation?
Hi Steve, it is a pier and beam foundation. I don't know if the piers were poured or on a block.
Thanks,
Lucy
Hi Lucy,
If you read the article below, you'll see that while your right that many people in the GBA community prefer sealed crawl spaces for a number of good reasons, vented crawls spaces can be healthy and efficient too. In both cases, the devil is in the details and if your project is going to be particularly difficult to detail for a sealed crawl space and you are concerned about flooding, a vented crawl space can work too.
In 2017, when I was still at Fine Homebuilding, our Best New Home of the year was a project in Austin designed and built by Eric Rauser and Matt Risinger using Joe Lstiburek's "perfect wall" approach. The house had a vented crawlspace with 1 in. of closed-cell spray foam. There is a link to that article below as well.
https://www.greenbuildingadvisor.com/article/building-an-unvented-crawl-space
https://www.finehomebuilding.com/2017/04/25/for-the-sake-of-simplicity