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How to Fix Mold Problems in Homes Built on Concrete Crawl Spaces

There are ways to reduce humidity and not have to deal with mold if your home is built on a concrete crawl space.

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Homes that have a concrete floor in their crawl spaces may end up having a mold problem. That’s because mold tends to form in warm and wet places. In fact, pumping concrete into a crawl space can increase your risk of having a damp foundation. Since concrete is permeable, water can find its way through the concrete slab and make the crawl space humid. 

It’s important to fix the source of this problem since mold and mildew can be rather harmful to your health. 

nasty wet crawl space

Issues with Concrete Slabs

Every homeowner with a crawl space knows that the dirt floor underneath their home can be a source of all kinds of problems. Therefore, it is no wonder that pumping concrete into a crawl space may seem like a good idea. Concrete slabs look good in basements and garages and give these spaces a nice, finished look. 

Many homeowners want to seal their crawl space since they can be wet, musty breeding grounds for mold, not to mention havens for pests. If you do not control the situation in your crawl space regularly, mold can easily migrate upward into your living space and turn your cozy home into a health hazard. Nasal congestion, coughing, wheezing, sore throat, headaches, and even fatigue are telltale signs that you have a mold problem on your hands. 

Unfortunately, a concrete slab in your crawl space can cause more harm than good. It is a known fact that every concrete mix contains a lot of water, so your concrete slab can easily saturate the entire area with mold-friendly moisture. 

Even if a construction team installs a vapor barrier before pumping concrete, problems can still occur. The same barrier will prevent concrete water from escaping into the soil, so it won’t have any other option but to move upward.  The concrete slab itself will contain moisture. A slab that’s 4 inches thick and covers a surface of 1,000 square feet contains 500 gallons of water. 

In addition, a temperature difference between the air and the concrete will cause condensation that can lead to mold growth. 

If you have a concrete slab in your crawl space, there are some steps you can take to keep your foundation mold-free. 

Checking for Cracks 

The first thing to do is to check for cracks in the concrete slab foundation. The most common way for the water to get into the crawl space and cause humidity problems is through the cracks. When you notice that water is pouring into the foundation, it’s best to call the professionals. 

It’s important to note that water can get through the concrete slab even if there are no visible cracks. That’s because concrete is a permeable material and water easily finds its way through it. 

Gutters and Drainage 

In areas with a lot of rainfall like Kansas City, MO water tends to accumulate around the structure’s perimeter and put pressure on the foundation. After a while, it will find its way through the concrete and create a humid environment for the mold to grow in. 

Gutters and drainage systems are the best way to prevent this from happening. They can be used to move the water away from the home, where it cannot cause any damage. Sometimes, you’ll also need a sump pump to help you remove the water collected in the sump pit in your crawl space. 

Encapsulating the Crawl Space 

Even when there are no cracks in the concrete slab, there’s still a chance humidity will get into the crawl space, and that’s why it’s important to seal it with a vapor barrier. This prevents most of the humidity from getting in and involves a relatively simple installation process. To completely encapsulate your foundation, our team will cover the walls and the floor with a plastic liner and seal any possible moisture entryways, such as doors and vents. 

Installing a Dehumidifier 

A dehumidifier is an appliance used to control the air humidity in your home. One can be installed in a crawl space and used to keep it dry enough so that the mold can’t appear. It’s best to consult the experts about the size and strength of the device since these depend on the size of your foundation and humidity levels in your crawl space. Ordinary, store-bought dehumidifiers won’t keep your crawl space dry. Instead, you will need a professional device that can dry out a larger, more humid space. 

Inspecting the Property Regularly 

All of the devices and measures we mentioned need to be inspected regularly to make sure they are still functioning properly. Even if your home is properly waterproofed and measures have been taken to reduce the humidity, you need to ensure regular maintenance.   

A homeowner can inspect their home on their own, but it’s best to have an expert check the draining system and the foundation so that nothing is overlooked. 

If your crawl space has a concrete floor, you may be struggling with excess humidity and mold growth. Contact us at Foundation Recovery Systems and schedule a free inspection and quote. Our expert will assess the situation in your crawl space and let you know what kind of work needs to be done to solve your moisture issues for good. 

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