Is There Mold in Your Home’s Crawl Space?
Updated: Mar 23
Mold loves hiding in dark, damp places. So it might not come as a surprise that mold could be hiding in your home’s crawl space. If a crawls space isn’t insulated, it can easily become damp with condensation. Leaky pipes or areas in the crawl space that are susceptible to rain or snow can also be sources of moisture. That dampness, combined with the darkness of the crawl space, could make it the perfect breeding ground for mold.
In this article we’ll talk about how to identify mold in a crawl space, what causes mold to grow in a crawl space, how to get rid of mold in a crawl space, and we’ll teach you how the professionals kill mold in a crawl space.
Is there mold in my crawl space?
Mold can be difficult to identify indoors. Identifying it in a dark, dirty crawl space can be nearly impossible if you haven’t been trained to do so. Something that might help you identify whether or not you have mold in your crawl space is the smell. Mold produces microbial volatile organic compounds (mVOCs) which is what gives it that musty smell. Poke your head in the crawl space through an access panel and see if it smells musty.
You may not be able to tell if there’s mold in your crawl space just by smell, however. Just because it doesn’t smell musty, doesn’t mean there isn’t mold growing somewhere down there.
Here is a step-by-step guide you can use to help determine if you have mold growing in your crawl space:
Bring a high intensity flashlight into your crawl space.
Look for any dark brown, black, or green patches of growth.
Check the floor joices and retaining walls for mold growth.
Place the flashlight flat against the surface of the joice or wall and shine it down the length of the wood.
Position your eye behind the flashlight, and look down the illuminated surface of the wood.
Using this technique, you should be able to spot any mold growing from the surface.
Be sure to wear the proper PPE before attempting this. Cover your head with a hat, or bandana, wear a facemask and goggles, and put on gloves just in case. Mold exposure can have adverse effects on your health. And do not attempt this if you are very old, or immuno-compromised, as you may be at greater risk of the effects of mold exposure.
What causes a moldy crawl space?
Humidity. If you have a high-humidity environment in your crawl space, the odds are good that you have mold. If you see puddles of standing water, then you’re almost certainly going to have mold in your crawl space.
Before you can even think about killing the mold in your crawl space, you’ll need to remedy any moisture issues. Leaky pipes, poor drainage, or rain and snow freely entering the crawl space will all cause mold growth. You should dry out the crawl space as much as possible to prevent the mold from coming back. Getting the humidity level in the air to below 45% is ideal. You can also check the moisture content of the wood in the crawl space with a surface moisture meter. You should aim for a moisture level of below 15% in the wood.
How to Get Rid of Mold in a Crawl Space
The best way to take care of your moldy crawl space is to call a professional. We have the tools, and specialized equipment to treat your crawl space without further damaging the structure of your home or accidentally pushing the mold from your crawl space into your home.
There’s very little you as a consumer can do to completely rid your home of mold. Without the expensive, hard-to-find chemicals and specialized distribution systems, you’ll be unable to fully kill the mold in your crawl space.
There are some things you can do to treat the surface mold in your crawl space, however. Here are a few things you may need for this job:
The proper PPE (gloves, mask, goggles, tyvek suit, etc.)
A good off-the-shelf antifungal mold remover
A HEPA air scrubber or a HEPA shop vac
A few stiff-bristle brushes
A pack of shop rags
Buckets, sponges, and spray Bottles
To prevent the mold from moving up into your home, you create negative air pressure in the crawl space. Meaning you should set up the HEPA air scrubber to draw air from the crawl space and blow it to the exterior of your home. Without that, the spores could drift up into the living area of your home once you start scrubbing it.
Follow the manufacturer's directions for applying the mold remover. Scrub it off with a stiff bristle brush, and wipe the area down with a rag. You can also use a HEPA vacuum cleaner or a shop vac with a HEPA filter to suck up the surface mold before scrubbing at it with a good stiff bristle brush.
As you can see, this process is time consuming, labor intensive, costly, and most importantly, it is a huge risk to your health and home. Mold in the structural components of a crawl space should be dealt with swiftly and effectively. Left untreated, it could rot away the support structure of your home and cause major issues. Tackling this mold problem yourself, in a tight area like the crawl space of your home also puts your health at risk.
If you find mold in your crawl space, we highly recommend having it dealt with professionally.
Mold in Your Crawl Space? Call our Fresno, CA Mold Experts
Our experienced technicians know exactly how to kill mold in a crawl space. At My Pure Environment, we use dry fog technology to blanket the crawl space with a powerful sterilant. The sterilant is composed of peracetic acid and hydrogen peroxide, disbursed in a fine mist of micro-particles. The particles are small enough to float into the cracks and crevices of your crawl space and they are also small enough to bounce off of surfaces.
This means that when we treat your crawl space for mold, we’re not adding any moisture, further exacerbating the issue. None of your wiring or plumbing will get wet during treatment, ensuring that everything stays safe and working throughout the process. Contact us today for a free consultation in person or remotely via a video conference call.