It's easy to ignore that cramped space, but moisture there can lead to mold. Here's how to prevent mold in your crawlspace before it becomes an issue.
Should You Be Worried About Mold In Your Crawl Space?
Updated on Aug. 18, 2021
When it comes to crawl spaces, I’m geographically lucky. I live in a desert environment, which usually keeps mold at bay. However, when I lived in Florida, it was a whole different story. With all of that humidity and rain, mold was an ongoing struggle.
The Secret to Preventing Mold in Your Crawl Space”Mold in crawlspaces is a pretty common issue,” says Bethany Uribe, an AHERA-certified building inspector at ASAP Restoration. “Most people don’t even notice it growing because they rarely go in this space, but for people who are sensitive to the health effects that mold can cause, even minute amounts can migrate and cause allergic reactions or worse.”
If you are worried about the potential of mold growing in your crawl space, here are some steps to prevent it, which could also save your mold problem from becoming larger and more costly.
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What Causes Mold in Crawl Spaces?
Humidity and moisture cause mold, so the more humid your climate is, the more likely mold is to be a problem. This is especially true if your crawl space is generally damp from nearby groundwater or condensation or has poor ventilation. Outside water getting in is often the culprit.
“Typically, there is a leak or a past flood that is causing the moisture level to be high enough that existing spores have a starting point to grow from,” says Uribe.
Tips to Prevent Mold in Crawl Spaces
The key to preventing mold in your crawl space is to make it drier, and there are several ways to do that.
Control Moisture
Check for places where moisture might be entering your crawl space, such as your walls, the crawl space ceiling, vents, cracks in your foundation and leaks around HVAC ducts, pipes and other plumbing components and fixtures. Also, make sure your gutters, downspouts, air conditioner condensation drain and sump pump drain are directed away from the house as far as possible.
“Ideally, this is at least five feet away,” says Chad Thielk, a home improvement expert with JustAnswer.com. “In some cases, you may also need a sump pump to remove excess groundwater.”
Increase Ventilation
The better the air circulates down there, the less mold has a chance to hang on. If you have egress windows in your crawlspace, open them regularly to keep the area less stagnant. Also, “have the dryer vent vented outside of the house and not into the crawl space,” says Melanie Powers, president at Goodberlet Home Services.
Install a Vapor Barrier
A vapor barrier between the crawlspace and the rest of your home probably won’t prevent mold in your crawl space, but it is likely to prevent mold from migrating from there into the living space of your house, says Thielk. “Encapsulate the crawl space by cleaning it out and installing vapor and thermal barriers inside, which will help keep it dry,” he says.
Use a Dehumidifier
A dehumidifier removes water vapor from the air, condenses it to a liquid, and drains or disposes of the liquid in a catch basin that can be emptied.
“This method is relatively expensive, since you need to keep a dehumidifier running regularly, but it is also one of the most effective at mold [prevention],” says Uribe.
Fix Foundation Drainage
If none of that solves the problem, you may have to take more drastic measures, like reformatting and sealing portions of your foundation or the drainage system around it that transports rainwater away from it.
“This may be the most expensive option there is, but if it’s the cause of the problem, then it will also be the only solution that works,” says Uribe.
FAQ
Can mold in my crawlspace be dangerous?
Yes, mold can be dangerous to your health. However, unless you are sensitive to it, there’s a good chance that when it’s in your crawl space, it won’t affect your health, says Uribe. “In fact, most insurance companies that have mold remediation in their policies won’t pay out for a mold remediation job in a crawlspace because it isn’t considered ‘livable space,’ and neither is the attic,” says Uribe.
That being said, it is prudent to prevent and get rid of mold in your crawlspace, so it doesn’t become a larger problem by traveling to spaces in your home where you do spend time.
How do I prevent mold after my crawlspace flooded?
Get rid of any remaining water with a pump, squeegee or vacuum and remove anything that is damaged or waterlogged. Next air out the space immediately with fans and dehumidifiers. The goal is to dry it out, which can be difficult because the area is so small and inaccessible.
Thielk recommends also treating the area with a mold-killing product such as Concrobium Mold Control. “A common misconception is to use bleach, which only treats surface mold and does not kill it at its roots,” he says.
Also, if you run into trouble drying the space out promptly, it might be time to call a restoration or water damage remediation company to help dry it out and prevent the spread of any spores.
About the Experts
Bethany Uribe is an AHERA-certified building inspector at ASAP Restoration in Mesa, Arizona. She has nearly a decade of experience in the construction and water damage mitigation industries.
Chad Thielk is a third-generation construction worker. He started in the industry at age 15 and worked for a commercial remodeling company before becoming a home improvement expert with JustAnswer.com, the on-demand platform for 24/7 help from pros.
Melanie Powers is president at Goodberlet Home Services, a female-owned plumbing, construction, electrical and HVAC repair company, serving parts of Illinois and Indiana since 1982.
