Many homeowners aren't aware that they have a crawlspace and some rarely go inside it. A crawl space is a hollow area found underneath the first floor of some homes. Crawlspaces are usually 1, 2 or 3 feet high—just high enough for someone to enter by crawling, as its name implies. Aside from elevating your home off the ground, a crawl space is a convenient and inconspicuous place to contain the "guts" of the house, such as the HVAC system, duct work, plumbing, and electrical wiring. Crawlspaces are also preferable to basements if you live in a damp location that experiences a lot of rain or is prone to termites.

However, it's important to know that proper ventilation of a crawl space is essential to protect the structural integrity of your home AND your health. Without ventilation, crawl spaces can give way to the "stack effect." The stack effect can be defined as a process where moisture moves from your home's lower level (crawlspace) through cracks in the floor and into your living area. A crawl space with excess moisture can be a breeding ground for mold, fungi, termites, and potentially even rodents.

How do moisture and condensation form in my crawlspace?


  • When your crawlspace is improperly ventilated, moisture and humidity will form in the open area creating condensation problems. Condensation can also infiltrate your crawlspace from the dirt on the ground which is rich in moisture.

How does moisture in my crawlspace affect my living area?


  • If the “guts” of the house are in your crawlspace and they are attacked by moisture, mold will begin to form on these “guts” since they are manufactured using cellulose rich materials that molds use as a food source. The "guts" of your house are compromised of the ductwork, piping and sometimes HVAC system. Your living area can also be compromised since the “guts” are what ventilate your home. Additionally, cracks and/or gaps in the foundation can allow easy access for moisture and condensation to travel into your living area.