A two aspect closed mobile foam is Utilized in all crawl space programs which offers a humidity barrier on any area in which the foam is used.  By way of example, alorair crawl space dehumidifier Sentinel HD55, You will find there's "User Manual Down load" within the still left Portion https://crawlspacewaterproofingse37047.birderswiki.com/1482438/the_2_minute_rule_for_crawl_space_repair_contractor