A vapor barrier's job is simple: stop the ground from breathing into your house. Bare crawl space soil releases moisture vapor constantly — and in Chattanooga's clay-heavy, high-groundwater terrain, that release never really stops. The 6-mil builder-grade plastic found under most homes was never meant to handle it: it tears during installation, degrades within a few years, and is usually laid loose with open seams that let vapor flow around it anyway.
We install reinforced 12–20 mil polyethylene barriers — three times the thickness of builder grade, with a cord reinforcement that resists punctures from service traffic. The barrier covers the entire floor, wraps every pier, runs up the foundation walls, and is mechanically fastened and sealed at every seam with butyl tape. That's the difference between a barrier that controls moisture and one that just covers dirt. If your crawl space also needs vent sealing or dehumidification, we'll tell you at the inspection — a barrier is the foundation of moisture control, but in our humidity it's sometimes not the whole answer.
Moisture readings, photos, and a written report — no obligation.
The free inspection tells you exactly what's going on — with photos and moisture readings, not a sales pitch.
12 mil minimum for real durability; 20 mil for high-traffic crawl spaces or rough ground. The 6-mil sheets sold at hardware stores tear during installation and degrade within years — they're false economy.
A quality installed barrier typically runs $1,500–$2,500 for an average home, depending on size and ground condition. The free inspection gets you an exact written number.
It depends on your moisture levels. If readings are moderate, a sealed barrier may be sufficient. If humidity is high or water intrusion is active, you'll need vent sealing, drainage, or dehumidification too. We measure first and recommend the smallest intervention that actually solves the problem.
A properly installed 12–20 mil reinforced barrier lasts 20+ years — versus 2–5 years for loose 6-mil plastic.