Protect your crawl space.
Protect your entire home.

Mil is a unit of thickness equal to one-thousandth of an inch. A 16 mil vapor barrier is 16/1000 of an inch thick — significantly heavier and more durable than the 6 mil poly commonly sold at hardware stores.

Thicker film resists punctures, tears, and long-term wear far better. 6 mil is a temporary ground cover; 16 mil is a professional encapsulation liner designed to survive crews crawling on it and decades of service.

Yes. Viper CS lays flat and cuts cleanly, so a careful homeowner can install it. Many homeowners hire an encapsulation contractor for full wall-and-floor systems, but a ground-cover installation is very DIY-friendly.

Each roll is 12 ft × 100 ft — 1,200 square feet of coverage before overlaps. Plan roughly 10–15% extra for seam overlaps and running the liner up walls and piers.

Yes. With a vapor transmission rate below 0.1 perms, Viper CS blocks water vapor rising from the soil — the primary source of crawl space humidity.

Mold needs moisture. By blocking ground vapor and lowering humidity, an encapsulated crawl space removes the damp conditions mold and mildew need to grow.

Yes. Viper CS works over dirt, gravel, and concrete. Over concrete it acts as a moisture barrier for slabs, storage areas, and basement floors.

Yes. The 16 mil virgin polyethylene construction is highly puncture resistant — it stands up to knee pads, tools, stored items, and service technicians moving through the space.

Installed correctly and protected from direct sunlight, a 16 mil liner is a long-term solution — typically lasting 20+ years, and often the life of the home.

Yes, for a sealed encapsulation you should overlap seams 6–12 inches and seal them with a quality poly seam tape. This keeps the system continuous and vapor-tight.

Absolutely — that is the recommended final step. Once the ground and walls are sealed, a crawl space dehumidifier maintains low humidity year-round with very little workload.

A sealed vapor barrier is a key component of radon mitigation systems, reducing soil gas entry. For known radon issues, pair the liner with a proper sub-membrane depressurization system.

Yes. 16 mil film is designed to be crawled on for inspections, pest control, and HVAC or plumbing service without tearing.

Yes. Viper CS can be mechanically fastened and sealed to foundation walls and piers as part of a full encapsulation system.

Viper CS performs from −40°F to 176°F, covering ground and crawl space conditions in every US climate.

Overlap adjoining sheets 6–12 inches, keep surfaces clean and dry, and seal with poly seam tape. Seal wall attachments with butyl tape or termination bars per local practice.

Polyethylene itself does not feed mold or bacteria, and by keeping the space dry it removes the conditions they need to grow.

No. Compared with standard 6 mil poly, 16 mil film has far higher tensile and tear strength — it is built for job site handling.

Yes. Viper CS is inert virgin polyethylene with no odor or off-gassing concerns, safe for enclosed crawl spaces and basements.

Yes. It is an excellent moisture barrier under basement flooring, across storage areas, and anywhere ground moisture threatens stored goods.

Store rolls indoors or covered, out of direct sunlight, and off sharp surfaces. UV exposure should be limited before installation.

Yes — Viper CS vapor barrier is made in the USA and stocked by D7 Supply, an authorized distributor with real inventory ready to ship.