Keeping Your Crawlspace Dry and the Bugs Out!

For many homeowners, a dirt crawlspace is the place the builder used to house the mechanical devices such as the HVAC unit, the water heater and plumbing pipes. Or it may be seen as a space that was built to elevate your actual living space off the ground to keep it dry.

But with how crawlspaces are designed, they don’t do a very good job of drying out after moisture enters. And a damp or wet crawlspace is not a great place for mechanicals. This is especially the case for areas with humid and warm climates. Instead, crawlspaces can become traps for moisture, and water that seeps up from the dirt floor can turn your crawlspace into a swamp.

As that moisture or water lingers around the crawlspace, it can do more than just encourage mold growth and wood rot. Through what’s called the Stack Effect, that excess moisture in your crawlspace can get sucked up into your living spaces, bringing with it increased humidity and any odors being produced such as by mold.

But did you know that moisture can also attract a variety of small pests who are looking for a place to nest? When moisture-loving critters start moving into your crawlspace, they can bring with them a host of problems. Let’s take a closer look into how to take care of your crawlspace’s moisture problems and how that will keep the creepy crawlers out of your home!

What Bugs Love Moisture?

For many living beings on this earth, moisture is necessary for survival. This is especially the case for a large variety of arthropod lifeforms such as different insects and arachnids. If moisture is allowed to build up in your crawlspace, it can become a magnet for certain creatures that require humidity in order to thrive. Here’s just a sample of what tiny pests can move into your crawlspace if the moisture is just right…


Whether you’ve seen them or know them by reputation, termites are something you never want in your home. While there are different types of termites in the wild, they all consume wood in order to live. Subterranean termites are one type that relies greatly on maintaining a humid environment to survive while they forage for food. They even build mud tunnels so that they can forage while keeping moisture levels around them stable.

For these moisture-loving termites, a damp crawlspace is like heaven. There’s the moisture they need to not dry out, and your crawlspace will have plenty of wood in its support structures. If your crawlspace’s wooden structures are left damp with moisture, it will be the perfect place for both food and building a colony. Left to their own devices, termites will tunnel their way throughout a damp wood structure as they create chambers and passages. The structural damage and the cost for repairs can be severe if they’re not dealt with promptly.

Dust Mites

With dust mites being so tiny, it can be hard to give them much thought. But these small creatures are quick to grow in numbers, and all they need is moisture and enough to eat. As dust mites live and reproduce, they produce fecal particles that can be easily swept up by the air moving up from your crawlspace into your home’s living spaces. These particles can trigger allergic reactions such as sneezing, and nasal congestion. They can also agitate asthma symptoms for those with asthma, such as having trouble breathing.


Like termites and dust mites, ants are particular about the humidity within their colonies. Moisture in a crawlspace can create an environment that’s friendly to them, making it easier for them to set up a colony and grow. Certain species of ants, such as carpenter ants, can also do a lot of damage to your crawlspace’s wooden structures as they dig out their tunnels and chambers. What’s more, as an ant colony grows, their foragers will continue to spread out until they find more food sources—such as in your kitchen!

How to Keep Your Crawlspace Dry

All the listed pests have one thing in common: the need for moisture to survive. If you can keep your crawlspace dry and clean, there’s a good chance that those pests will look elsewhere as they search for food sources and new places of shelter. But how can you keep that moisture and humidity out of your crawlspace? Encapsulating your crawlspace can be the answer! Here’s how you can get to preparing your crawlspace to be encapsulated…

  • Seal any crawlspace vents. While they are meant to help air circulation, unfortunately they do more harm by letting outside moisture in.
  • Seal any gaps in walls around any piping running from your crawlspace to the outside. This will also prevent outside moisture from seeping into your crawlspace.
  • Clean your crawlspace of any organic debris.
  • Fix any leaks you may have in your crawlspace, such as leaky plumbing.
  • Inspect your electrical wiring and electrical equipment in your crawlspace.

Once your crawlspace has been prepared, your crawlspace can now be encapsulated with a vapor barrier lining. These linings are made of plastic and should be thick enough to remain intact for an extended length of time. But you should be aware that there are different vapor barrier linings with different degrees of thickness and durability. It is important to make sure that you don’t get one that’s too thin or permeable, otherwise moisture will simply seep right through it and dampen your crawlspace.

You should also consider getting a crawlspace waterproofing system installed if your crawlspace is prone to flooding. Encapsulation will not be enough to prevent your crawlspace from filling with water if you tend to have groundwater seeping up from the ground. With a proper crawl space waterproofing system, groundwater can be diverted to a sump pit where it can be pumped out and away from your home. This will allow your crawlspace encapsulation to do its job of keeping moisture vapor away from your useable crawlspace.

Finding an Expert in Crawlspace Encapsulation and Waterproofing

As you can see, the condition of your crawlspace can have long-term effects on the rest of your home. From mold to pests, a damp crawlspace can become a haven for these problems which can cascade into structural damage and even adverse health effects. While you can try to encapsulate your crawlspace on your own, it might not be as effective as an expert’s handiwork. You’ll want to make sure that no outside moisture is able to invade your crawlspace. What’s more, waterproofing your crawlspace can be a challenge to do on your own, and it will require tools and techniques that would be better with training and experience. Should you need an experienced crawlspace expert that offers a strong warranty and has the thousands of positive reviews to back their work, consider giving ’58 Foundations a call!


Jeff Campbell