A damp crawl space is a problem that can affect a home in three main ways. First, it’s a natural catalyst for mold growth, which can create noxious odors and potential health issues. Second, it can result in damage to your walls and ductwork when left alone for an extended period of time. Finally, it can reduce the functioning of your home’s ducts and lead to energy loss.

This means spending more money on your heating and cooling bills. If your home has a damp crawl space, it’s often because of no insulation or inadequate insulation. Here are some ways that you can correct this problem and optimize the efficiency of your crawl space.


Preventing water from entering should be done first because the impact of insulation will be minimized if it consistently accumulates moisture. That’s why you should direct all water sources away from your crawl space the best you can. Some examples include periodically cleaning gutters so excess water doesn’t spill over, and lengthening downspouts far enough away from your home so water can’t collect. Typically, eight feet away from the foundation is sufficient.


When choosing insulation, it’s smart to go with polyioscyanurate because it’s resistant to water damage. This is superior to other insulation like fiberglass and should prevent mold from forming in the future. You should hang insulation from the top of the walls all the way to the bottom. Leaving an extra two feet extending at the bottom should optimize the efficiency even further and reduce the likelihood of a damp crawl space.

Moisture and Vent Covers

Placing a moisture cover over the floor of your crawl space will take it one step further. In the event that people routinely walk through this area, it’s best to choose a thick moisture cover that can handle the activity. Finally, you should install vent covers on the exterior of vents and fill any cracks with caulk or sealant.

For more expert advice about crawl space insulation and other issues related to home comfort, please contact us at Apollo Home Heating, Cooling and Plumbing. We’ve been serving the Greater Cincinnati area since 1910.

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