Question: how much does it cost to install vapor barrier under house?
Answer: Crawl space encapsulation costs $3,000 to $8,000 on average, with prices ranging from $1,500 to $15,000. Crawl space waterproofing costs $3 to $7 per square foot for a drainage system, insulation, vapor barrier, repairs, sealing, and dehumidifier. A vapor barrier costs $2 to $4 per square foot to install.