Several books conflict on how or if to use a vapor barrier on fabricating a inside wall against a basement wall. Ex. vapor barrier against concrete then insulation, insulation against concrete then vapor barrier, no vapor barrier and build wall one inch away from basement wall. Which one is the best? If you leave the one inch gap seems like that would be a great place for spiders to proliferate, how do you avoid that? I live with some arachniphobias.