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dehumidifier in crawl space

Why You Need a Crawl Space Dehumidifier

Excess moisture, musty odors, mold, and other problems are common in vented dirt crawl spaces. Along with encapsulating your crawl space, you can improve the overall air quality and prevent unhealthy conditions by installing an energy-efficient dehumidifier! Learn more here.

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What Causes Crawl Space Moisture?

Building homes with open crawl space vents has been a long-time building practice, with the intent of drying the air under the house. But it has been found that this does more harm than good. Warm, moisture-filled air from the outside enters through open vents and mixes with the cooler air in the crawl space. As that air is heated it increases the relative humidity level. Molds and wood-rotting fungi thrive at 50% +RH (relative humidity). The nasty, heated air rises through your house and ends up being part of what your family breathes in the living area! 

Why Do I Need A Crawl Space Dehumidifier? 

Are you concerned about the quality of the air in your home? You might be breathing in toxins that can cause serious health problems for you and your family. Mold, dust mites, rodent waste, and radon gas are just a few of the things that could be lurking in your crawl space.

Believe it or not, over 50% of the air you breathe indoors comes from the crawl space beneath your house, thanks to the stack effect. That’s why it’s so important to ensure that your crawl space is free of moisture and humidity. If your crawl space is vented and has any kind of moisture, you’re creating the perfect conditions for mold and wood-rotting fungus growth, insect and rodent infestation, and damaged structural supports.

Mold growth can lead to problems with asthma and allergies, and can also attract bugs that feast on the mold and destroy wooden supports. Rotting wood beams and floor joists can threaten the stability of your home. Ineffective insulation due to moisture and insects can also raise your heating and cooling costs.

But there’s good news! JES has the solution to all of these problems with our crawl space dehumidifier. Our innovative system eliminates moisture in your crawl space and is designed to work with our other crawl space repair and encapsulation solutions.

With the JES crawl space dehumidification system, you won’t have to worry about breathing in toxins or dealing with structural problems caused by moisture and mold. Don’t wait any longer to improve the health, stability, and function of your home’s crawl space. Schedule a free inspection with one of our professional consultants today! 

Why Choose a JES Crawl Space Dehumidifier?


The JES Crawl Space Dehumidifier works to clean and filter the air, control moisture and humidity, remove odors, and prevent mold and mildew growth. The overall air quality throughout the rest of your home also will be improved. 


This dehumidification unit is designed for long-life operation in damp crawl spaces or basement conditions. Like all the solutions we install, the unit comes complete with a warranty and its operation and maintenance can be ensured by regular check-ups from our service technicians.


Our dehumidifier may be powerful, but it is an energy-efficient model that meets and exceeds ENERGY STAR® efficiency requirements. It can remove approximately 100 pints of water per day, as well as help you lower your energy and electric bills.  


The JES dehumidifier is self-draining and can be directed to drain into the crawl space waterproofing or sump pump system, or a condensate pump can be installed. That means there are no buckets or reservoirs of water that you need to empty. The unit also has an internal fan that is insulated to significantly reduce operational noise.

How Does a Dehumidifier Factor in Crawl Space Encapsulation? 

Once the crawl space has been sealed, it’s important to condition the air. Dubbed “the cherry on top” by industry professionals, a crawl space dehumidifier completes your crawl space encapsulation needs. With all things considered, dehumidifying your crawl space is the fourth and final step to crawl space encapsulation. 

Used in conjunction with the JES CrawlSeal™ Encapsulation System, the JES Dehumidifier works by removing and eliminating air moisture in your crawl space, draining the excess water to your sump pump system or outside. This discourages insects and rodents and makes your home a healthier place to live. Its other benefits include that it also protects the structural integrity of your home and can reduce energy costs from 15 – 25%! 

The truly unique aspect of a crawl space encapsulation dehumidifier is the fact that you never have to empty a bucket of water from your crawl space again. You don’t have to worry about controlling the water on your own because the dehumidifier releases the water through its own release mechanisms, whether it’s your sump pump or a condensate pump. 

crawl space dehumidifier

How Can I Keep My Home Dry and Healthy?

If you have been experiencing crawl space problem signs such as wet crawl space insulation or high indoor humidity, it’s important to properly address these issues with the right solutions. 

For excessive moisture and water, we waterproof the crawl space by placing the CrawlDrain™ perimeter drainage system in the crawl space floor to catch seeping water. This water is then directed to drain to a sump pump system, and it is then pumped out of the crawl space and away from your home’s foundation. 

It’s also important to seal the crawl space. Airtight vent covers are placed on the home’s exterior to conceal the vents, and then the crawl space is encapsulated. We use the JES CrawlSeal™ Encapsulation System. This durable 20-mil liner is placed on the crawl space walls and floor to completely isolate the area from the earth. CrawlSeal™ serves as a moisture and vapor barrier, and it helps insulate the crawl space. Rigid ExTremeBloc™ insulation panels also can be placed on the walls for the best protection. 

Crawl Space Dehumidifiers


When it comes to protecting your crawl space from unwanted damage, there are a few different solutions available to you. If you have standing water in your crawl space, for example, you may want to invest in a heavier-duty waterproofing measure—but then again, only after you’ve worked with a contractor to patch up the leak or crack allowing moisture into your home. Some of the best home waterproofing measures include:  

When Can Dehumidifiers Help Your Home?  

In some situations, however, a dehumidifier can help you better control the level of moisture entering your home. If you’re dealing with high levels of humidity, or if you want to get ahead of the kind of damage that can compromise your home’s structural integrity, then you can install a dehumidifier in your crawl space.   

Provided that you’ve fitted your dehumidifier to your crawl space, this unit can pull pints of water out of the air on a daily basis, preventing the growth of mold and the development of wood rot all the while.  

Covering All the Bases  

Note that dehumidifiers on their own may not always serve as perfect waterproofing solutions. You may also want to pair your dehumidifier with a vapor barrier and interior drainage if you want it to work more effectively. When paired with other home waterproofing measures, dehumidifiers live longer and tend to protect your sensitive crawl space more effectively.  

Of course, dehumidifiers and other crawl space waterproofing measures are only effective when you’ve properly attended to the damage that’s allowing moisture into your home. When in doubt, reach out to a professional contractor in your area to determine whether your home requires additional repairs before you install your dehumidifier.

While high levels of humidity in your crawl space can lead to damage, humidity isn’t always bad. You need to maintain a consistent level of humidity throughout your crawl space if you want to create a healthy environment throughout the rest of your home. 

Maintaining a Healthy Level of Humidity 

Don’t try to suck all the moisture out of your crawl space, though. While limiting the amount of moisture that makes its way into your crawl space is a good thing, eliminating it entirely can cause your unprotected wooden supports and exposed concrete to become brittle. 

Instead, set your dehumidifier to 40-50 percent humidity. This level of humidity will keep the materials in your crawl space hydrated without providing wood rot or mold the dampness they need to start growing. 

Adjusting Your Humidity as Necessary 

You’ll know something is wrong in your crawl space when you can’t maintain a consistent level of internal humidity, even with a dehumidifier. If you notice your humidity levels starting to rise, then you may have a crack or leak somewhere in your crawl space. 

Identifying this damage takes a bit of time, especially if you don’t have professional experience backing you up. Some leaks can send moisture into your home from your foundation, while other times the pipes in your crawl space may be the source of your damage. If you notice the levels of humidity in your crawl space rising, reach out to the professional contractors in your area for guidance. With a little bit of work, you should be able to lower your humidity back into a safe range, near 50 percent.

You do not want to use a typical home dehumidifier to protect your crawl space from moisture 

damage. These types of dehumidifiers are not powerful enough to remove incessant moisture from your crawl space, nor are they designed for standard crawl space conditions. Instead, if you are interested in installing a dehumidifier, talk to area professionals about the dehumidifiers that may better serve your home. 

Taking on Damage Before Installing a Dehumidifier  

Commercial dehumidifiers are rarely strong enough to protect your crawl space from unwanted moisture. Our teams do not recommend using these types of dehumidifiers even as temporary waterproofing measures due both to their ineffective nature and due to the damage they can take on trying to clear out your crawl space. 

If you want to try and protect your crawl space from additional damage before installing a non-commercial dehumidifier, you have a few options available to you. Ideally, you’ll want to work with the professionals in your area to repair any cracks or leaks that you’ve found in the space. If you try to implement any waterproofing measures before investing in these types of repairs, you can damage those measures and limit their lifespans. 

Pairing Your Dehumidifier with Other Waterproofing Solutions 

As mentioned, typical home dehumidifiers cannot help you entirely control the moisture in your crawl space. If you do install a non-commercial dehumidifier in your crawl space, though, you may still want to pair it with additional home waterproofing measures like a moisture barrier or encapsulation. These measures limit how the humidity is getting into the crawl space. 

Some of the best waterproofing measures to pair with a non-commercial dehumidifier include: 

  • Vapor barriers – thick, plastic-like material placed over the walls and floor in your crawl space to keep water, moisture, and most gases out of your home. 
  • Interior drains – drains that intercept leaking water before it reaches the rest of your crawl space will help keep it dry and free of damage. These work best when paired with a sump pump. 
  • Sump pumps – these appliances are essential in preventing leaking and flooding in your crawl space. Any water intercepted by the interior drainage system will be directed to drain into the sump pump system so it can be properly removed from the crawl space and away from the home.

When you start looking for a dehumidifier to place in your crawl space, you’ll want to know that you’ve invested in a system that can not only pull moisture from the air but that can work with any other waterproofing measures you have in place to reduce the risk of mold and structural damage throughout your home.  

Size Does Matter  

You’ll also want to take this time to determine how powerful you want your dehumidifier to be. The options provided by JES Foundation Repair work well in smaller crawl spaces. If you live in an area that sees a significant amount of rain over the course of a month, however, that you may need heavier waterproofing measures to ensure your crawl space doesn’t get so humid in the first place. 

Function is Important 

Typical dehumidifiers have buckets or reservoirs of the collected moisture that need to be emptied regularly. If you rarely go into your crawl space, this can be problematic. That’s why it’s important to have a unit that you can essentially “set and forget.” The dehumidifiers installed by JES Foundation 

Repair are self-draining and can be directed to drain into a sump pump or condensate pump. 

If you’re not sure where to start when shopping for a dehumidifier, you can collaborate with a professional contractor working in your area. Together, you can inspect your crawl space for signs of damage and determine how powerful (and with how many other solutions) you need a dehumidifier to be.

Other Dehumidifier Considerations 

Many homeowners assume they can use a regular household dehumidifier to address their crawl space moisture issues, but unfortunately, that’s not the case.

The truth is, crawl spaces have unique humidity levels, and moisture accumulates much faster there than in other parts of your home. That’s why household dehumidifiers just don’t cut it in crawl spaces. The components needed to make a dehumidifier effective, such as the cold coil and fan, are too small to keep up with the job, and you’d have to keep emptying the reservoirs constantly to avoid overflow or flooding.

That’s where the JES crawl space dehumidifier comes in, offering comprehensive benefits that work hand in hand with crawl space encapsulation.


JES Can Help You With Your Crawl Space Repairs!

Are you ready to improve the health of your home by tackling your crawl space moisture? Contact JES today to schedule a free inspection and estimate with our expert team! We’re here to help you find the perfect solution for your crawl space, and find out the source of your moisture issues.

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