Does air just happen to move from the crawlspace in to the house? Actually all buildings operate off of the same principle called the “Stack Effect”. That means that normal air flow moves from the bottom and sides to the top. 40 -50% of the air in the house at any given time is from the crawlspace. Obviously, this allows mold and other contaminants to move right into the house.
Some of the Negative Effects of a dirt crawlspace:
- Musty Odors
- Toxic Mold
- Bugs, dust mites, and rodents
- Odors in upholstery and carpets
- Swollen doors and windows
- Cupping wood floors
- 15% increase in power bills (approximate)
- Health risks from allergies to cancer
Crawlspace Encapsulation is the only real solution to the dirt crawlspace and could be the most important decision you ever made with home ownership. Our first priority at PureAir Systems is insulation removal and wood treatment of the subfloor and joists and any other wood structures. The wood is at first properly cleaned and then we apply our permanent adhesive mold block. This protects the wood against mold and wood decay with a 25 year warranty.
Foundation Ventilation
The only reason crawlspaces have foundation ventilation is because of the dirt under the house. Think about it, if you had a fully finished basement with sofas and a big screen TV, there would be no foundation vents, because the builder knows that the vents would allow mold and moisture inside and contaminate the entire basement. There is no dirt floor because the concrete slab separates the dirt from the basement and it works just fine and protects the home. Foundation ventilation is a dead give-a-way that there is dirt in the crawlspace. Dirt means vents, no dirt means no vents. The dirt is the problem.
In the summer, outside hot humid air comes into the crawlspace thru the vents. When it is raining the situation is even worse. Most crawlspaces have air conditioning ducts allowing the hot humid air and the evaporation from the dirt of the crawlspace to hit dew point near the cool air ducts and condensation results. This condition now allows mold from the dirt below an ideal environment to begin growing on the subfloor and wood supports of the house. Eventually wood rot can ruin the subflooring and joists.
There are three types of mold groups; primary, secondary, and tertiary. As mold gets established, the more toxic ones often begin to set in. The wood floor allows air and toxic mold to move right into the house, but even worse all air conditioning ducts leak and blow soil gases and mold evenly throughout the house.
Why would anyone ever build a house over dirt in the first place? It is cheaper than a concrete floor. The damage to the house and people living in the house is never worth a cheap dirt crawlspace. In fact, every dirt crawlspace needs to be completely sealed or encapsulated to prevent all of these problems permanently.
