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  • Writer's pictureLaura Redd

With Summer comes humidity… What is going on under my house?

Air conditioning keeps your house cool when the humidity goes up, but when the humidity under your house goes up, big problems can occur. Keeping the unseen areas nice is just as important as ordering a new rug for the living room. So let’s look at another level of ugly design.

Crawl space humidity has been plaguing homes in North Carolina and Virginia since the first day they were built.

As the humidity levels rise in crawl spaces, moisture condensates on the surfaces, leading to serious problems in your home. These problems can lead to health issues and the need for expensive repairs. Some of the crawl space problems are mold and mildew, allergens and even rotting wood. But how do you stop these things from entering your crawl space? We used to believe that having vents in our foundation gave air flow and would allow the space to dry out. Now we know that the open vents actually cause higher levels of humidity.

When the humidity has been left unaddressed, the crawl space will begin to sag, creating uneven floors above. In some extreme cases, sections of the floor may even begin to cave in! Additionally, many pests (termites, carpenter ants, wood-eating beetles, crickets, et al.) love rotting, moldy wood.

As the mold and rot increases sometimes animals begin to live (and die) in your crawl space, odors will begin to rise into your home along with the crawl space air. Mold is a known allergen, and can significantly affect anyone in the home who suffers from asthma or allergies.

Another side effect of crawl space humidity is an increase in your home’s cooling bills. Have you ever seen water dripping from a window-mounted air conditioner? This is because a large part of the job of an air conditioner is to dehumidify the air it cools. Humid air is much more expensive to cool than dry air!

The best way to cure the humidity issue under your home is to seal the space. Add a vapor barrier, which is a plastic barrier placed on the floor of the crawl space to prevent moisture from seeping into the area, or a more extreme option is to seal up the space entirely and place a dehumidifier under the house to lower the humidity. The correct amount of humidity for a crawl space in North Carolina is under 70%. After you take care of the vapor barrier and seal up the vents, the humidity levels well drop and you can remove the dehumidifier. The dehumidifier should be removed after the level drops.

I know this is not pretty design but we have to take the good, bad and ugly sometimes to make things beautiful.


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