[Greenbuilding] Crawlspace foam insulation -- how much?

[Frank Tettemer]

Hi Leslie,

You may want to re-consider the idea of foaming the floor in a crawl 
space. My concerns would be that the foam would act too well as a vapour 
barrier, and you may have moisture/mildew problems down the road in the 
crawl space. I AM in Canada, so your geographic climate might create 
different problems than here.

I always design any neccessary crawl spaces as a definite part of the 
conditioned space of the home. That means insulating the walls and the 
floor of the crawl space, and leaving the floor as a vapour-open plane, 
as well as including the crawl space in the heating design. This avoids 
condensation trouble, by keeping the air warm and dry.

Frank

Frank Tettemer
Living Sol ~ Building and Design
www.livingsol.com
613 756 3884


On 12/06/2015 2:02 PM, Leslie Moyer wrote:
> I am in NE Oklahoma.  I'm in the process of getting estimates for 
> crawlspace insulation in the floor joists--closed cell foam.  My crawl 
> space is dry now that we've fixed some plumbing problems, but I'm 
> having some cupping issues with some wood flooring and part of the 
> fiberglass batts that were originally in the house when we bought it 
> were taken out over time for this and that. Anyway--closed cell foam 
> seems to be the best solution.
>
> The first guy who came this morning wants to quote me 1.5" foam, 
> though said he would quote 2" if that's what I really want, saying 
> that would be enough for "Canada".  I understand about the benefits of 
> air sealing, but I was still thinking I would need more inches of foam 
> according to what I've read on R-value & this area.  Thoughts?
>
> -- 
> *Leslie Moyer*
>
>
>
> _______________________________________________
> Greenbuilding mailing list
> to Send a Message to the list, use the email address
> Greenbuilding at bioenergylists.org
>
> to UNSUBSCRIBE or Change your List Settings use the web page
> http://lists.bioenergylists.org/mailman/listinfo/greenbuilding_lists.bioenergylists.org

--