A crawl space vapor barrier is a moisture-proof barrier, sometimes made of plastic sheeting, that is placed on the floor of the crawl space area.  The vapor barrier separates the crawl space from the ground below.  Our CleanSpace Encapsulation System is made of a 20-mil plastic, similar to a pool liner, that is permanently attached to the floors and walls of the crawl space giving you extra protection from moisture that can cause mold, mildew and musty odors.