Buying a House with a Crawlspace? Look For These Problem Signs

Purchasing a home can be thrilling but also daunting. Even when a house looks like a dream come true, you’ll want to make sure that there are no significant problems lurking beneath. For a home with a crawlspace, those underlying problems can be quite literally under your feet. That is why you should always make sure to check for crawlspace problem signs.

Let’s investigate what you should look out for to make sure there’s no unwanted surprises when you purchase a house with a crawlspace…

Crawlspace Problem Signs to Look Out For

There are a variety of potential problems that could be found with a thorough crawlspace inspection. Have a look at some common examples…

  • Mold
  • Wood Rot
  • Pests including ants, termites, dust mites, and rodents
  • Damaged foundation


Each of these crawlspace problem signs can lead to their own additional problems. Mold, for example, can release mold spores into the air as it grows and colonizes. These spores not only help mold spread, but they can be an airborne allergen that can trigger allergic reactions as well as asthmatic symptoms. Some mold species have been known to also cause further illness to those with compromised immune systems.

Mold is another crawlspace problem sign for homes with wet crawlspace problems
A common moisture-related crawlspace problem sign is mold on wooden structures.

Mold tends to come in a variety of colors (white, yellowish, greenish, and black molds are common), but they usually can be spotted because of how they stand out against the color of the surface they’re growing on. Black mold stands out more clearly, where a white mold might be more difficult to detect.

Here are some of the common household molds that you may encounter…

  • Black mold / Stachybotrys chartarum
  • Penicillium
  • Aspergillus
  • Wood Rot
About Wood Rot

Wood rot is another fungal problem that can be found in crawlspaces. These fungal species get their name from how they live by growing on damp wood and beginning the rotting process. As wood rot consumes certain parts of the wood its growing on, the wooden structure eventually begins to break down and even crumble away.

In nature, this is how dead trees and plant matter can return to the soil. But in a home, this can spell trouble if it’s a floor joist or any other part of the above flooring system that’s being gradually weakened by wood rot.

If you feel the upstairs floors bouncing, or you see that the wood floor is cupping or warping, this is most likely due to the crawlspace below. It could be from wood rot, or it could be from the support columns in the crawlspace. Either way, have your home inspector or a crawlspace expert take a look.


From insects and tiny mites to rats and mice, there are a lot of critters out there that want nothing more than to find a nice place to nest and feed. Termites will want to dine on the wooden support structures of a damp crawlspace. Meanwhile, ants will eventually expand their foraging range into your living space to find more food for a growing colony.

A crawlspace is also the perfect dark space for rodents to hide out. But in their efforts to make a nest, rodents may use all manner of things to make their home. This can lead to structural damage as well as damage to equipment and belongings. Their droppings and urine can also carry diseases.

Dust mites are so small that their fecal particles can get carried by the air flowing from your crawlspace into your living space. This air flow is caused by the Stack Effect (or chimney effect), where the difference in temperature and air pressure causes your home to suck air upwards like a vacuum. As you can see, there are many ways that pests can make trouble for your crawlspace as well as the rest of your home.

Damp crawlspaces can mean mold on insulation and wooden support structures. Look out for these signs!
Watch out for problem signs like moldy insulation or moldy floor joists


Damaged Foundation

Another crawlspace problem sign to look for is damage to the foundation. Keep an eye out for cracks—they can be a sign that your foundation has been experiencing a lot of hydrostatic pressure from outside groundwater. These cracks can also be a sign of the settling of the foundation. In both cases, repairs need to be made to stabilize the foundation from further damage.

The Source of Crawlspace Problems

All these problems can present a challenge to enjoying a new home. But these different scenarios rely on the same source: excess moisture in the crawlspace.

Whether it is humid air flowing into the crawlspace through its crawlspace vents, groundwater seeping under the walls or up through the dirt floor, or water leaking through a crack in the foundation—these can all add to the moisture in your crawlspace air, leading to the problems described above.

The Solution? Crawlspace Encapsulation and Waterproofing

While a dehumidifier may come to mind, it won’t work if the source of intrusive moisture or water isn’t remedied. That’s where crawlspace encapsulation and crawlspace waterproofing can help. With a thick vapor barrier lining, outside moisture can be kept out of the crawlspace. Meanwhile, with crawlspace waterproofing, outside groundwater can be controlled so that it’s redirected out and away from your home. This will protect your foundation from problems caused by hydrostatic pressure.

Make Sure Your Next Home is a Safe and Healthy Home

To ensure a smoother transition into your new home, check on every part of the home including the crawlspace. Have the home properly inspected to make sure any crawlspace problem signs are discovered and addressed. Due to how air flows upwards from the crawlspace via the Stack Effect, what’s in your crawlspace has a direct effect on the air quality and comfortability of your home. Moisture-loving pests also bring their own set of problems.

To get your crawlspace encapsulated and/or waterproofed, with the strongest warranty, decades of experience, and thousands of happy customers, call 866-367-7606 or contact us online for a free crawlspace estimate!

Crawlspace encapsulation can help prevent moisture-related problems from returning
An encapsulated crawlspace is a neat, clean, and comfortable one. It becomes a usable space for whatever you desire!