Crawl Space Don'ts - Crawl Space Bad Building

• Don't put a vapor barrier or rigid insulation board on the ceiling of your crawl space (unless your home is on stilts).
• Don't close vents without sealing the earth off.
  
• Don't seal the earth off without closing the vents.
• Never use a fan to blow outside air into your crawl space.
• Never use a fan to blow air out of your crawl space if the make up air is coming from outside.
  
• Don't install a liner or concrete without removing organic material such as wood, cardboard, insulation, etc., from the dirt floor first.
• Don't depressurize a space that has combustion appliances (more than one pascal)