According to this belief, crawl spaces need to be protected from ground moisture by the way of a ground vapor barrier (usually a 6 mil plastic sheet) and should be allowed to “breathe” through open vents. This belief says that open vents will dry out the space by allowing outside air to circulate within the crawl space.

It may sound like it makes sense; after all, air is known to dry things. A breeze will dry the clothes on a line and opening a window in the house will help dry out your freshly shampooed carpet, right? However, in a crawl space environment things work a bit differently that they would in open air or at the above floors.

At any given season, there is always a significant difference between the temperatures in the crawl space and the temperatures outside and on the floors above. Such differences in temperature cause the moisture present in the air that comes from the outside to condense all over the surfaces within the crawl space. The wooden joists and insulation will soak up the moisture, grow mold and rot.

Advanced Energy has devised a list of ways to tell that your crawl space is in desperate need of service:

• Mold or moisture damage in the crawl space or living area
• Musty odors in the living area
• Condensation (“sweating”) on air conditioning ductwork or equipment
• Condensation on insulation, water pipes or truss plates in the crawl space
• Buckled hardwood floors
• High humidity in the living area
• Insect infestations
• Rot in wooden framing members

The only proven method to protect crawl spaces from moisture is encapsulation and conditioning. Conditioned crawl spaces also help improve indoor air quality and make your home more energy efficient. The savings on energy bills alone will pay for the cost of encapsulation overtime.

Article originally published here: http://www.basementsystems.com/press/view.php?id=152