Unvented, Conditioned Crawlspaces...

What do you guys know about “Unvented, Conditioned Crawlspaces?” I ran into my first one the other day, and although I didn’t see anything that out of the ordinary, that is for the exception of insulated foundation walls instead of the the flooring, and no ventilation, I didn’t see anything else that alarming. But I figure I better learn more about them now. Anyone got any experience with them?

Thanks ahead of time for any input,
Ed

http://www.bestofbuildingscience.com/pdf/Closed%20crawlspaces%20do%20double%20duty%20HEM_SP05_p32-36.pdf

http://www.justcalllarry.com/pdf/HomeEnergyDryingoutacrawlpace.pdf

http://www.advancedenergy.org/portal/crawl_spaces/pdfs/Double%20Duty.pdf

Thanks Roy!

Check to make sure that is conditioned, served by HVAC for the house, such as one or more supply ducts and a return air or opening to the rest of the house that allows the air in the crawlspace to be exchanged and conditioned. Crawlspace temperatures should be within a few degrees of the house. Cold spots are where condensation will occur. Bare dirt should be covered, a concrete slab is preferred, but heavy plastic is probably OK if it is sealed with tape or glue. There should not be any standing water.