Signs of Crawl Space Problems

Approximately 15 percent of homes in the United States have crawl spaces as a foundation. Crawlspaces not only provide a foundation for the home, but they also supply an important buffer between the ground and the house above it.

Many crawl spaces are vented to the outside in order to allow air to circulate below the house. However, when moisture from the air, or the ground accumulates in the crawl space, it can have detrimental effects on the structure of the home and the air quality inside the property.

So how do you know if you have problems in your crawl space? There are several common signs of crawl space problems.

Vapor Barrier enclosed crawl space

Moisture In The Crawl Space

Water in your crawl space can be caused by a number of factors. A recent storm may be the starting point of standing water, but you should also check for plumbing leaks or flooding. What’s more, the hydrostatic pressure in the ground beneath your crawl space can cause standing water.

crawl space with light and hanging insulation

This can be especially problematic if you notice that the insulation has become wet which can lead to a slew of other issues. (See the condensation area below.)

High Humidity In Your Home

Since humidity is the concentration of water present in the air, moisture in the crawl space often leads to higher levels of humidity in your home. Based on the principles of air movement (warm air rises and is replaced by cold air) approximately 50% of the air that starts in your crawl space will end up in your home.

If your skin feels clammy or the windows in your home are foggy, the humidity in your home is too high and this may be an indication of moisture in your crawl space. It’s important to check on this because air not only carries moisture, it can carry other harmful elements including mold.

Mold and Mildew

We all know that mold spores grow when they land on surfaces that are wet. Not only is mold unsightly, it can be dangerous to your health. As the air travels from your crawl space up through your home, it can carry with it mold spores, producing air quality issues in your living space. 

Even if you can’t see the mold spores, you may be able to smell them.

Musty Odors

As mold and mildew grow, they release horrible-smelling gasses that not only attach themselves to fabric, but also travel through the air. If you start smelling these musty odors, it is important to check for mold and/or mildew in your crawl space. 


When the moisture in the air becomes too heavy, condensation is soon to follow. This condensation will start to collect on surfaces in your crawl space leading to mold and wood rot.

If you observe insulation that is sagging in your crawl space, there’s a good chance that moisture has settled on the insulation and it has become too heavy to stay in place. Not only does wet insulation lose some functionality (up to 40 percent of its R-value), the moisture in the insulation can also damage the wood surrounding that area.

Wood Rot and Floor Joist Problems

One thing leads to another when it comes to moisture in the crawl space. As the water collects on the surface of the wood or in the insulation, it can begin to damage the wood that supports your home. 

If you have noticed that your floors seem bouncy, uneven, or sloping to one side, this can suggest an issue with your floor joists. It’s important to have this resolved in order to protect your home.

Higher Than Normal Energy Bills

Have you noticed an increase in your energy bills? It may not just be the kids leaving lights on all over the house and forgetting to shut the door. 

As we mentioned earlier, wet insulation can lose its R-value preventing it from properly maintaining the temperature in your home. Additionally, when air becomes too humid, it becomes more difficult for your HVAC unit to condition the air. This can lead to higher energy bills with an air conditioner that is constantly running.

Next Steps For Crawl Space Problems

If you have identified that you are experiencing one or more of the crawl space problems listed above, there are several crawl space repair solutions available. It’s best to work with a professional crawl space repair company to ensure you implement the right solution for your specific situation. On top of that, crawl spaces are typically small spaces that are difficult to work in. Professionals will have the tools and experience necessary to repair your crawl space.

How Long Can You Wait To Repair A Crawl Space With Problems?

Most foundation repair companies offer free inspections, so the first step is to identify the problem. Depending on the issue, repairing your crawl space may become a top priority. Standing water from a recent storm may not be as critical as a serious mold infestation or sagging floor joists or beams. It’s important to have the area inspected by a professional to protect your home and the people that live there.

Need someone to check out your crawl space? Locate your nearest crawl space expert now

Frequently Asked Questions About Crawl Space Problems

What can go wrong with a crawl space?

The most common problems with crawl spaces include mold that can spread through the air to your home and moisture which can ruin insulation and rot the wood beams that support your house. If your crawl space has a dirt floor with no vapor barrier, these commons are much more common.

Should I worry about my crawl space?

Crawl spaces may not be the most pleasant place to spend your time, but they should be inspected on a regular basis to check for the presence of moisture, mold, or wood rot. It should be fairly easy to spot these types of problems, but you can also inspect it by checking for musty smells which would indicate the presence of mildew and/or mold.  If your crawl space has a concrete base floor, it should also be inspected for foundation cracks.

How can I improve my crawl space?

There are several ways to improve your crawl space and protect the foundation of your home. Some methods include:

  • Crawl space encapsulation
  • Dehumidifiers & Fans
  • Vapor Barriers
  • Drainage systems including interior drains
  • Sump Pumps
  • Systems designed to move water away from the foundation of your home such as french drains

More information about crawl space repair solutions can be found here.

Can crawl spaces have foundation issues?

Since the crawl space is the foundation of your home, the answer is yes. Crawl spaces contain the support joists and beams for your home and can experience some of the same issues as basement foundations. Additionally, crawl spaces are generally subject to more moisture and mold issues than basement foundations, especially those with dirt floors and no vapor barrier. One of the main culprits of foundation issues is moisture in the crawl space. Too much moisture in the crawl space can cause condensation which can eventually lead to wood rot on your beams and joists. Homeowners typically will notice these issues in the home in the form of sloping floors and/or floors that feel bouncy. Foundation issues in the crawl space also can manifest themselves by sticking windows and doors, along with drywall cracks.