Unsealed 6-mil ground cover

Most crawl spaces have a 6-mil vapor barrier on the dirt. It is about the thickness of a trash bag and is unsealed at the seams or to the walls and piers and often is staked down creating additional holes in the liner. These gaps and holes that are unsealed allow moisture from the ground to get into the crawl space and affect the joists, insulation, and cause mildew/mold growth.