Vapor barrier installation in Hanahan SC - ground moisture kept below the liner

Yes, a plastic ground cover belongs in a vented crawl space just as much as a sealed one, so the liner comes first and closing the vents is a separate choice you can make on top of it. In vented crawl spaces the bigger source of moisture is usually water running in from grading that slopes toward the house, no drainage around the foundation or sprinklers soaking the walls, so a good plan looks at those along with the liner. I'd rather fix the water first than lay plastic over a puddle.

Federal guidance for this work calls for sheeting at least 6-mil thick, a mil being a thousandth of an inch, and 20-mil is considered the heavy-duty choice for rough crawl spaces where someone goes under often for service. Thicker liner holds up better over the long run, while thinner liner is easier to handle and costs less. At the estimate I'll point out which one fits your crawl space and why.

A mechanical drying system keeps it dry, and ENERGY STAR guidance on closed crawl spaces gives a supply of conditioned air or a dehumidifier as examples, so if you close the vents, plan for one of them along with the liner. The same guidance recommends leaving a termite inspection gap at the top of the perimeter wall so termites are easier to spot. If your house has had a termite treatment, tell us early, because South Carolina's termite treatment standards include a crawl space vent requirement that has to be completed or waived on homes already built.

Move anything you've stored under the house and any loose junk you can easily reach, since a federal guide to closing crawl spaces starts with belongings and debris out of the way. After that, old insulation and old plastic come out and the floor gets graded so the new liner lies flat. When I come out, we'll sort out what you move and what our crew hauls off.

There's no one price, because it comes down to the size of your crawl space, the liner thickness you pick and how much prep and water work has to happen before the plastic goes down. A plain liner over a clean, dry floor sits at the lower end, and closing vents, adding a drying system or fixing drainage first all add to it. Your written estimate shows what you'd be paying for, and I'll tell you straight if a piece of it isn't worth the money for your house.

Ask whether they're set up with the state for this work, since South Carolina counts skilled specialty work a homeowner hires out over $500 as residential specialty contracting. The state also calls for a $5,000 surety bond once a project's total cost, labor and materials together no matter who buys the materials, goes over $5,000. We're fully licensed and insured, our work is satisfaction guaranteed, and I'm glad to answer anything about how we're set up before you sign.