I just contacted with Neutocrete (http://www.neutocrete.com/ ) to deal with my dirt floored, uninsulated crawlspace. Has anybody here ever dealt with them. My father has been in home construction and remodeling for 40+ years and recommended them to me. The crawlspace is bitter cold and has been home to many critters over the years. I think that getting it sealed form the outside and made part of the conditioned space will make a huge difference in keeping that end of the house warm. I'll post pics and a review after the job is done in a couple weeks.