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waterproofing installed in crawl space

Crawl Space Waterproofing Solutions

Learn why it is important to have reliable waterproofing solutions in place to keep your crawl space and entire home safe, dry, and healthy.

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Crawl space water is the source of your crawl space’s #1 enemy – humidity.

If you’re having any problems in your crawl space, it’s a good idea to start looking at crawl space waterproofing solutions. Waterproofing comes with a variety of benefits and avoiding the waterproofing process can come with its own unique challenges.

waterproofing installed in crawl space

There are many reasons crawl space waterproofing should be at the top of your to-do list. If you’re not already convinced, consider these things to think about when considering whether you should waterproof your crawl space.

Crawl Space Water: Problems & Solutions

Learn about issues with water in your crawl space, how waterproofing this area helps your home, and what solutions are available to you.

What happens if you choose to just ignore the crawl space water problems you’re having right now? Bad news: It’s just going to get worse. 

Ruins Crawl Space Insulation

Crawl space water almost always ruins the insulation inside. Crawl space insulation protects the air in your crawl space from becoming warm and muggy, but wet crawl space insulation does almost nothing.

That can have a significant impact on your crawl space. 

Insulation is an important part of your crawl space, and it’s important that you maintain its strength. If you’re seeing crawl space insulation problems, you need to notice these issues, fix the root cause, then replace the crawl space insulation.

Rots Wood

Wood rot and similar fungus or insect infestations happen most commonly in warm and wet situations. Plus, wood holds onto water for a long time. If you have a damp crawl space, you’re likely to end up with wood rot because the dampness will probably leech into the wood, creating the perfect place for wood rot to take root.

It’s also important to note that wood rot isn’t the only potential problem wood can end up with. Many different fungal and insect-based infestations can cause similar problems, and wet crawl spaces can even contribute to the natural degradation of the wood.

Creates an Environment for Mold and Dust Mites

Another pest-related concern is mold and dust mites. Both of these are incredibly bad for allergies, skin issues, and respiratory concerns. In fact, if you tend to have reactions to existing pests or dirt in your home and you have a dirt crawl space, you’re almost certainly having allergic reactions because of these pest concerns.

Mold and dust mites are very common in wet crawl spaces. After all, mold typically requires a very high level of moisture to grow and thrive. If you haven’t spent time making sure the levels of moisture in your crawl space are low, you’re essentially inviting mold in.  

Rises Through Your Home

The stack effect happens when you have openings in both your crawl space and your attic. Air enters the crawl space of your home, and as it warms up, it rises until it escapes out the attic. It’s an effect that happens in all homes with openings in the crawl space and attic.

When you have a clean crawl space with no openings, you don’t have to worry about the stack effect. However, if there are mold spores, dirt particles, and dust mites in the crawl space, the stack effect will bring these all the way up through your home, causing it to get dirty and cause respiratory issues.

There are a variety of benefits that crawl space waterproofing can provide. These are the top reasons to waterproof your crawl space.  

Added Selling Feature

Though it’s a relatively minor benefit, it’s still true that crawl space waterproofing lends an added selling feature to your home. People are more likely to purchase a waterproof home than a non-waterproof home, all things considered.

This makes it a great decision to waterproof your crawl space whether you’re already interested in selling your home or not. Either way, it’s a useful feature that you can add to your crawl space. Whenever you go to sell your home, you’ll be able to put that on the inspection.

Lower Energy Costs

It takes more energy to cool and condition air with high humidity. That’s one of the reasons Advanced Energy studies suggest you could save 15-25% on your energy bills every year if you encapsulate your crawl space, which includes waterproofing.

This should be a huge reason for you to make the choice for crawl space waterproofing. Even though it can cost money up front to waterproof your crawl space, it will pay for itself over time with lower costs for energy.

Enhanced Comfort  

When you invest in crawl space waterproofing, you’re sealing off the cold ground with a water vapor barrier, which keeps this cool air trapped outside of your crawl space. The warmer air rises, which typically makes your floors warmer during the winter.

Additionally, during the summer, you also won’t have to worry about warm air coming into your cooled home through crawl space vents. That can make the home feel much more comfortable. It’s a great choice for better comfort year-round.

Better Air Quality

Over 50% of the air you breathe comes from your crawl space in some way, which means it’s important to pay attention to the health of that air. When you don’t have a waterproofed crawl space, it’s common for the air to contain a wide variety of allergens like mold spores.

Waterproofing enhances your crawl space’s air quality. With waterproofing, you no longer have to worry about whether your crawl space has mold spores, dust mites, or similar creatures that thrive in wet and moist environments.

It can be tempting to avoid waterproofing because it seems like a problem that only “certain crawl spaces” have. However, if you have any of the following things in your crawl space, it’s important to invest in waterproofing.

Dirt Crawl Spaces

If you have a dirt crawl space, there’s no way you’ll be able to make your crawl space completely free of moisture. Moisture in the earth goes down extremely far, and even if you’re able to dry out the top layer of moisture, it’s still going to come back up at some point.

Any homeowner with a dirt crawl space needs to make sure they’re laying down a crawl space vapor barrier. With a crawl space vapor barrier, all moisture from the earth stays on the outside of the vapor barrier rather than coming into the crawl space. From there, you can get to work on making sure your crawl space stays truly dry.

Crawl Space Vents

It’s common for people to have crawl space vents in their homes. For a long time, people felt like letting the crawl space “breathe” was crucial if you wanted to avoid crawl space moisture. To this extent, many new constructions had crawl space vents to allow for air circulation, and the process continues even today.

However, modern research shows that crawl space vents are much more trouble than they’re worth. Many crawl space experts now recommend that you cover your crawl space vents instead of letting them stay open. If you let your crawl space vents stay open, it’s very possible that you’ll end up with more crawl space moisture than if you were to close your crawl space vents and encapsulate the space entirely.

 Leakage or Crawl Space Water

Of course, if you’re already experiencing water in your crawl space, you can’t just put in a dehumidifier and hope for the best. Standing crawl space water of any kind is bad for the crawl space because not only does it contribute to higher levels of humidity, but it can also cause water damage at any of the places that it touches the walls or the floor.

First off, to handle water leakage, it’s important that you fix any leaking pipes or condensation on the outside of pipes. However, if you’ve already done that, it’s possible that there’s some sort of deeper problem you’re not seeing. You may need to install a sump pump or some other method of removing water from the crawl space.

The waterproofing process can seem confusing to anyone who hasn’t learned much about it. There are four main steps to take to waterproof your crawl space.

 Install Sump Pump and Remove Leaks

The first step is making sure you remove all standing water in the crawl space. Standing water will make it so that the crawl space never really gets dry; after all, that water needs to go somewhere, and most frequently, it attempts to evaporate into the air.

Removing leaks, especially plumbing leaks, will help you avoid this problem. You may also want to install a sump pump, which can pump standing water out of your crawl space. It’s best to pair a sump pump with an interior drainage system like the JES CrawlDrain™ system. CrawlDrain™ catches leaking water throughout your crawl space perimeter and then channels it to a sump pump system to be properly removed from the crawl space.

Add Vapor Barrier Liner

Next, it’s important that you add a high-quality vapor barrier liner. This is especially crucial if you have a dirt floor in your crawl space, and even if you already have a vapor barrier liner, you may need to add a new one if you don’t have one that’s of high enough quality.

JES uses the 20-mil CrawlSeal vapor barrier, which more effectively protects your crawl space from moisture rising up from the dirt. Remember that there’s no way to dry out a dirt crawl space completely. You have to install a vapor barrier; ideally, a 20-mil vapor barrier, if you want to make sure water moisture doesn’t come in from below.

Cover Crawl Space Vents and Doors

You also need to cover all your crawl space vents and doors. In the past, it was very common to build homes with crawl space vents; in fact, these were typically treated as the baseline, with encapsulated crawl spaces rarely mentioned, if at all. However, in more recent history, most people have started to realize that crawl space vents do more harm than good. 

Allowing your crawl space to “breathe” doesn’t really do anything, and crawl space vents can cost your home a lot of money, time, and effort. It’s important that you install crawl space vent covers and that you manage your crawl space doors so that no air or water can get inside.

Set Up Dehumidifier

Lastly, even if you’ve fully encapsulated your crawl space, you might want to set up a crawl space dehumidifier in the space. A crawl space dehumidifier can further help you in your journey toward making sure you don’t have water damage and similar water concerns in your crawl space. 

With a dehumidifier, you can make sure you know your crawl space’s humidity levels at all times. That’s extremely helpful because it means you’ll be able to monitor what’s going on and avoid having humidity concerns that you never noticed.


It’s clear that waterproofing your crawl space is a much better choice than choosing to leave it alone. Instead of just waiting for the crawl space water to damage the area, you can take a proactive approach and make changes that will result in a waterproofed crawl space.

Waterproofing your crawl space is definitely the best idea in these situations. After all, waterproofing not only helps you fix problems you might already be having, but it also helps you avoid future problems. All you need to do is schedule an inspection with JES. You’ll be able to learn more from a crawl space repair expert who will help you through the process.

We now have a crawl space to be proud of and feel very secure that we will not have any future problems. Pauline and I will not hesitate in recommending your company to anybody. We thank you for your services.

~ Burt & Pauline S., Williamsburg, VA

Looking For Local Crawl Space Waterproofing Contractors In Virginia, DC, Maryland, or Northeastern North Carolina?

At JES Foundation Repair our team of in-house crawl space waterproofing experts have warranted solutions for crawl spaces and foundations of all types.

We’re proud to serve all of Hampton Roads, from Virginia Beach throughout Williamsburg and surrounding areas; Northern Virginia, DC, and Southern Maryland.

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    Our Locations


    8361 Town Center Ct
    Nottingham, MD 21236


    311 Central Rd.
    Suite 2-02
    Fredericksburg, VA 22401

    Hampton Roads & NE NC

    2569 Quality Ct
    Virginia Beach, VA 23454

    Northern VA & DC

    7940 Gainsford Ct.
    Bristow, VA 20136


    309 Quarles Rd
    Ashland, VA 23005

    Southwest Virginia / Roanoke

    2033 Cook Dr.
    Salem, VA 24153

    Western Virginia

    456 Old Courthouse Rd
    Appomattox, VA 24522


    45 W Boscawen St,
    Winchester, VA 22601