Conditioned Crawl Spaces vs. Vented Crawl Spaces

[rwalter]

Ok most of the things I read say that a conditoned crawl space is the best way to keep down moisture and prevent mold. However tthere still are many who recommend vented crawl spaces.  I know John has a conditioned crawl space in his solar salt box home.  What are your opinions on this issue? This house will be built in upstate NY. Thanks

[Mudball]

I'm by no means an expert but I have done a good bit of reading about crawl spaces and basements. I cant find a site that shows the steps to build them but anyway...Every recent study performed showed results that a crawl space is better off to be insulated from the outside and there was studies showing no mold when the crawl space was NOT vented.
I will see if I still have some of those sites.

[Mudball]

Here is one of those sites I use to have. There are other as well.
http://www.southface.org/web/resources&services/publications/technical_bulletins/CI-Crawlspace%2000-774.pdf

[Daddymem]

There are some articles on foundations and conditioned crawlspaces here (and a lot of other topics).  I have not read them, I just stumbled on them this morning.

http://www.buildingscience.com/resources/resources.htm

These are the same people who did "Houses that Work."

[John Raabe]

Just added this to the referral page. Thanks for reminding me Daddymem.

Mudball - I have used the option 3 interior batt insulation system (shown in your southface link) on my own house. In recent client houses (and if I were doing my own again) I would use exterior foam insulation. It seals the crawlspace much better and requires less checking and patching.

[rwalter]

Thanks everyone with your replies. I had already read the report at www.buildingscience.com but thanks for posting it for the everyone.   Its an excellent model and it is what I am basing my design thoughts on.  The also have a nice video at www.hgtvpro.com on the best practice methods for crawl space foundations.

http://www.hgtvpro.com/hpro/pac_ctnt_ihdr/text/0,,HPRO_20976_28891,00.html?cat=0


I had not seen the one Mudball posted that very interesting reading as well.


I was leaning toward insulating the inside walls with foam. I am planning on using 7 courses of 10" block so in a few years from now if I want to jack the house up I can add 4 more course and have a full basement.  In NY they lowered the amount a  structure can cost to $10,000 (from $20,000) on non-stamped designs. Anything over $10,000 requires an architect's stamp on the drawings. My building inspectors being nice and I am real close to that figure so my project is ok with out stamped drawing. Any way I price it a full basement right off the bat wouldn't fly with out the stamped drawings.  

[rwalter]

One other aspect that I am thinking of doing is insulating the floor. I start by first putting down a 6 ml poly vapor barrier which will be fasted to the walls with adhesive and wood strips. After that by put down 4'x8' sheets of 2" thick foam insulation, followed by stone and a concrete floor.

[rwalter]

Here is another link.

http://www.hgtvpro.com/hpro/bp_foundation/article/0,2617,HPRO_20146_3463221,00.html