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Crawl Space Mold

Mold is one of the most common problem signs in a crawl space since these foundations are often exposed to moisture from the air or the ground.

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When you notice mold on your food, the first thing you do is throw it away. You might go so far as to clean the area that the food was located in for extra measure. Well, imagine mold growing inside your crawl space. You’d want to get rid of it as quickly as possible, especially since about 50% of the air in your home comes from the crawl space. FSS has solutions that prevent mold from ever growing in your crawl space. Read on to learn more about this common problem sign. 

What Exactly is Mold?

Mold needs two main components to survive – humidity and organic material. Unprotected crawl spaces contain both of these, so it becomes very easy for mold to grow below your home. All it takes is for humidity to enter through an open vent or leaking water to seep into wooden beams. Once mold is able to grow, it spreads quickly.

Eventually, mold spores travel up from the crawl space and spreads through the air in your home. Not only is this dangerous for your health as you breathe in mold spores. In fact, 50% of the air in your home comes from your crawl space. Mold below your home also leads to mold growth in other areas of your living space. That’s a sight no one wants to see, and you’ll end up paying for mold removal and repairs. But what causes mold in your crawl space? Here’s what to look out for.

What Causes Crawl Space Mold?

Crawl Space Vent

Open Crawl Space Vents

Crawl space vents are located on the foundation walls of your crawl space. In the past, crawl spaces were designed with open-air vents because contractors thought it would allow humid air below your home to easily escape. Unfortunately, the opposite ended up happening; open crawl space vents actually allow humid air to permeate your crawl space when the air outside is humid. San Antonio and Austin experience moderate amounts of humidity during the summer, humidity rises in your crawl space and gives way to mold growth.

Soil Washout

Soil washout is the term used to describe what happens when water breaks down the structural integrity of soil. While rainfall isn’t particularly high in Southeastern Texas, when it does eventually come, it can displace soil particles in your yard and turn the ground muddy. As water drains into the soil, it travels below your crawl space. Eventually, some of this groundwater evaporates and becomes trapped in your crawl space. Humidity levels rise below your home and create the perfect environment for mold to grow.

Leaking Pipes

Many important systems are located in your crawl space, including plumbing lines. If an appliance in your home starts to leak, the water is going to drain through the floor and into your crawl space. Sometimes, the leak itself might even occur in your crawl space, which allows massive amounts of water to drain into the foundation at one time. As water collects below your home, humidity levels rise, wood rot breaks down support beams, and mold is provided with the perfect breeding ground. Stop these leaks from occurring with crawl space encapsulation – a mix of vapor barriers, dehumidifiers, and crawl space drains that move leaking water away from your crawl space.


None. Having any mold in your crawl space becomes a major health hazard to anyone living in your home. Even the smallest amount of mold releases spores into the air, which are eventually carried into your living space through a process known as the Stack Effect. Once these spores are released, mold can begin to grow exponentially if no steps are taken to protect your crawl space. Long story short, any amount of mold in your crawl space is a bad thing.

Mold in your TX crawl space can appear as black or green splotches across many surfaces. Usually, mold will grow on organic matter such as wooden support beams in your crawl space. Eventually, these splotches will spread onto foundation walls, insulation, pipes, and other important surfaces below the home. Unfortunately, most people don’t even see mold until it spreads into their home. If you see mold growth around your house, make sure to have a professional inspect your crawl space for the same issue.

Don’t attempt to treat mold in your crawl space on your own. Mold is toxic to humans and can damage, skin, lungs, or eyes depending on the type. Moreover, using homemade cleaning solutions may not solve the problem completely. Crawl spaces are hard to traverse without the proper training, so for your safety, we recommend hiring a professional mold removal service that has dealt with crawl space mold before. After that, investing in crawl space encapsulation from FSS can prevent mold from ever growing in your crawl space again.

How FSS Stops Mold

Protecting your crawl space from mold is one of the most important investments you can make. It keeps the air quality in your home safe and healthy, and prevents your foundation from experiencing major damage. FSS has an expert team with years of experience dealing with crawl space encapsulation. We keep your crawl space dry with world-class solutions. FSS has vent covers that prevent humid air from seeping into your crawl space and providing fuel for mold growth.

We also offer a vapor barrier which creates an impenetrable wall between your crawl space and evaporating groundwater. Interior waterproofing also defends against groundwater by quickly draining it away from your crawl space before it can be absorbed as food for mold. Lastly, we install a dehumidifier which actively removes moisture from the air in your crawl space, effectively removing any chance for mold to grow.

Explore Solutions

Using crawl space solutions from FSS, you don’t have to let mold overtake your crawl space. We use crawl space encapsulation, a combination of vapor barriers, dehumidifiers, crawl space vent covers, and more to stop moisture from collecting below your home. All of our solutions effectively prevent mold from having any chance at growing because they remove a key ingredient that mold needs to survive.

Call FSS to Prevent Mold Growth in the Future

Crawl space mold can look scary and cause problems in your home, but you don’t have to suffer forever. FSS is a trusted source for crawl space repair for our neighbors in San Antonio, Austin, and surrounding areas. With expert knowledge, and over 20 years of combined experience, our team will keep your crawl space permanently dry. Contact us today to learn more about crawl space solutions and to schedule a free inspection.

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