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Want to Avoid Moisture Problems? Get Crawl Space Humidity Right

Find out the importance of maintaining the ideal crawl space humidity in your home.


Let’s face it. A lot of people struggle with crawl space humidity. They’re just not sure what the right humidity level is. Too much of it and the crawl space gets damp and moldy. Too little of it, and the wood supports dry and fails. 

Here, we’re going to look at the ideal humidity levels for the crawl space and what you can do to keep moisture at a minimum. 

crawl space encapsulation

What’s the Ideal Humidity Level?

It’s essential for you to maintain crawl space humidity levels of between 30 and 50 percent, leveling it out at 55%. If you can keep humidity levels within the above range, you will avoid moisture problems and some of the nasty issues that accompany it. 

Mold will start growing as soon as humidity levels cross the 60% mark. It will maintain a consistent humidity level and help you lower utility costs. Be sure to check the crawl space for leaks. A drafty crawl space will make your dehumidifier work extra hard. 

To maintain the ideal humidity levels, you will need a dehumidifier with a sensor. The sensor will monitor the moisture levels down there and prompt your dehumidifier to dry out the air if it’s extreme. 

Can Crawl Space Humidity Be Too Low? 

Yes, humidity can get lower than usual, and this isn’t good for the wooden joists and beams in your crawl space. Your home or building requires a certain amount of moisture. This moisture is necessary for acclimation purposes. If the wood’s moisture content drops below five percent, your joists or beams could warp. You need to keep it at five to 12 percent. Another thing you should know is that you can’t dry out the crawl space completely. What you can do is dry the crawl space and bring down the moisture levels than its previous levels.  

Cures for a Damp Crawl Space 

Here is what you need to do to keep the crawl space humidity within acceptable levels. 

Dehumidify the crawl space 

Once you seal the crawl space, ask your contractor to recommend and install the right dehumidifier for you. This appliance will help you keep the crawl space moisture in check. When the crawl space gets humid, its sensor will activate the machine. Your device will dry out the air and bring down the humidity to acceptable levels. The dehumidifier will shut off automatically once the job’s done. This feature can help lower your energy consumption and reduce your HVAC’s workload. Dehumidifiers are rated at 80 degrees Fahrenheit and 60% relative humidity. As the air cools or becomes dry, their efficiency will drop. 

Seal crawl space cracks and gaps 

The other thing you should do is seal the cracks, crevices, and openings on your crawl space walls. These will let in water and moisture during summer and spring. While you’re at it, ensure there are no plumbing leaks in the crawl space. They can easily dampen the crawl space and turn the floor into a waterpark. 

Encapsulate the crawl space 

Your crawl space will remain susceptible to outside air and moisture, both of which have a damaging effect on your home. It’s also going to be difficult to tame the conditions down there. To crown your waterproofing  efforts, make sure you seal the crawl space with a plastic barrier. A typical barrier is 20-mil and goes over your crawl space floor and wall. A material this thick will cut off outside air and pests. Our solution comes with a mold-resistant additive and is tear-proof. Once we install it, recurring moisture issues will be a thing of the past. 

Need help in controlling moisture? 

Keeping the crawl space humidity levels at an optimum can feel like a full-time job if you have a full plate or a busy schedule. That’s where we come in. Contact the crawl space experts at JES Foundation Repair for a free inspection and quote. 

We’ll send our crew to come and check the crawl space and identify moisture sources. They will carry out necessary repairs, then deploy the right waterproofing solution so your crawl space stays dry all year round. 

Don’t let moisture, mold, and other issues damage the crawl space and render it useless. Get in touch with the experts at JES Foundation Repair for a free assessment and quote. Our crew will come over and check the crawl space condition and tell you what’s ailing it. 

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