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9 Signs Your Crawl Space Has a Problem

nasty crawl space

If your home was built with a crawl space, it could be viewed as a blessing and a curse. While this area elevates your home and houses essential utilities, it can also harbor harmful crawl space problems like mold and rot.

These issues aren’t confined to your crawl space; they affect your entire home, creating an unhealthy and unsafe living environment for your family. But don’t get discouraged. Local crawl space experts can help you transform this area and protect what matters most.

We’ve compiled a list of signs to look out for to help you address crawl space issues before they get worse. 


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Top 9 Crawl Space Problem Signs

Crawl space problems come in all shapes and sizes, and you can spot them throughout your home. Here’s a list of the top nine signs your crawl space has a problem.

1. Sagging Floors 

When you walk across some areas of your first floor, do they feel bouncy and unstable? Have you also noticed visible dips in the floor or gaps between the floor and wall? Sagging floors are common because of problems with crawl space floor joists. Whether they are made of wood or metal, floor joists can easily succumb to the presence of excessive crawl space moisture and humidity, as well as termites and other pest damage. 

drywall crack

2. Drywall and Other Cracks 

Similarly, any problems with the supports in your crawl space can lead to additional issues throughout your home. Drywall cracks in the walls and off of doorways and window corners could be connected to weakening crawl space floor joists and supports. They could also be caused by foundation problems like settling. 

3. Condensation on Windows 

Most crawl spaces are exposed to the outdoor environment, meaning it’s easy for moisture to get into your crawl space. Unfortunately, that means the moisture can also get into your home. When too much moisture rises up into your home from the crawl space, you might notice condensation forming on windows (or other surfaces). 

4. Increased Humidity

If the inside of your home feels like a balmy summer afternoon, there’s too much moisture and humidity in the air that likely originates from the crawl space. The ideal humidity range for a home is 40 to 60 percent. Humidity levels above 60 percent lead to a damp environment and increase the chances of musty odors and mold growth.

mold in a corner

5. Mold Growth 

Mold spores can circulate from the crawl space and throughout the rest of your home. This growth thrives in humid areas with organic material it can use to sprout and spread, so a crawl space is the perfect breeding ground. Mold will often latch onto moist areas like bathrooms and kitchens, so keep an eye out in these places especially.

6. Cold Floors in Winter 

Outside air tends to influence the temperatures in a crawl space. Without effective insulation, the crawl space can quickly become cold on a winter day. You’ll notice this when you walk in your home—the floors will be cold to the touch. This indicates that your crawl space doesn’t have any protection from the outdoor environment, so just imagine what it will be like when a wet, humid day rolls around!

7. High Energy Bills 

When your crawl space has high amounts of moisture, it’s going to translate into high energy bills. Humid air will rise up into your living space and permeate nearly everything in your home. This can increase the temperature in your home as well. Your HVAC system will have to work on overdrive to keep equilibrium, resulting in higher than normal energy bills

8. Musty Odors 

Even after a thorough cleaning, do you still notice unpleasant, musty odors throughout your home that you just can’t seem to pinpoint? It may not be an old pair of shoes or a forgotten gym bag. Nasty smells from wet or moldy insulation, pest waste, or other nuisances could be wafting up from your crawl space.  

pests in a crawl space

9. Pest Infestations 

Whether we like it or not, as homeowners, spotting a bug here and there is going to happen. However, it turns into a major issue when you see large amounts of the same pest in your living space.

Pests are drawn to crawl spaces because they provide darkness, moisture, and shelter. But if pests aren’t dealt with, they leave behind waste in your crawl space and eventually make their way into your home looking for food. When this happens, it may be because of your crawl space.

What Causes Crawl Space Problems? 

Crawl space problems happen for many reasons, but they typically occur because of fatal design flaws. Since the mid-20th century, crawl spaces have been built with open vents and dirt floors. Leaving the dirt exposed was generally cheaper than covering it or pouring concrete. The open vents were intended to allow air to flow freely throughout the space to reduce moisture and humidity. But foundation experts have found the reverse is true. Open vents only allow water, pests, and unconditioned air into the space to wreak havoc on your home.  

When there is too much humidity, moisture, or water in the space, it can lead to damage, including rotting wood and sagging floors, energy drains, pest infestations, mold growth, unpleasant odors, and more. 

A vented crawl space also fuels the stack effect, the natural flow of air from bottom to top. Because of this, half of the air in your home comes from your crawl space. That means anything in your crawl space, like unpleasant odors, mold, and mold spores, are also circulating in the air throughout the rest of your house. This can lead to or worsen lung and breathing conditions, including asthma and allergies. 

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How Can Crawl Space Problems Be Fixed? 

The first step in remedying any crawl space problem is to have a professional inspection. Your local Groundworks company can provide a free inspection with one of our highly trained and experienced experts.

Our inspector will complete a thorough evaluation of your home inside and out, including your crawl space. That way, they can determine what’s going on, what caused these problems, any potential future issues that may arise, and the best way to solve them. 

We provide reliable crawl space repair and encapsulation solutions that are proven to permanently protect your crawl space and home, including:

Each solution is fully customizable based on your home’s needs, and they carry long-term, nationally backed warranties. 

Contact Groundworks for Lasting Crawl Space Repair

A wet, nasty crawl space is a danger to your family and home. Don’t neglect warning signs or delay repairing this area of your home. If you notice any of the signs mentioned here and suspect there might be a problem with your crawl space, contact your local crawl space repair experts for assistance.

Groundworks has extensive knowledge about common crawl space problems and how to solve them permanently. You can count on our teams to treat your home with the utmost care and create a healthier home for you and your family. Contact us today to schedule your free inspection and repair estimate! 


We recommend yearly inspections to catch and address crawl space problems early. Groundworks offers free, no-obligation inspections, as well as annual maintenance appointments to ensure your crawl space remains in good condition.

We don’t recommend inspecting or repairing your crawl space by yourself. You risk exposure to dangers like mold and pests, and DIY installations often do not properly address the root of the problem. Groundworks experts are equipped with the right tools, training, and safety gear to handle all your crawl space issues. Contact us for a free inspection and estimate.

Groundworks provides professional-grade solutions tailored to your home’s specific needs, ensuring long-term effectiveness and reliability. Our team of experts uses advanced techniques and high-quality materials that DIY options cannot match. Contact us today to schedule a free crawl space inspection and learn more about how we can help.

Holly Richards-Purpura

Holly Richards-Purpura

Content Writer

Holly is a Content Writer for Groundworks who has written and edited web content for the foundation services industry for almost 10 years. With a background in journalism, her passion for the written word runs deep. Holly lives in Columbus, OH, with her husband. Along with educating homeowners, she also has a big heart for the Big Apple.