Vapor Barrier
Definition
A vapor barrier is a sheet material — typically reinforced polyethylene at 6-mil to 20-mil thickness — installed to prevent moisture migration from soil or humid air into building assemblies. In crawl spaces, the barrier covers ground and wraps up onto foundation walls.
Common Questions
Real-World Example
You'd see this when a homeowner in Camas, WA notices musty smells coming through the floor — CRM Services inspects the crawl space and finds a torn 6-mil vapor barrier that needs replacement with reinforced 20-mil material.
Why It Matters
Vapor barrier installation is a core line item in CRM Services' crawl space and foundation remediation work across the PNW.
Related Services
Related Terms
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