You may not want to think about it, but the odors and gases (and all the critters) in your crawl space have a free pass into your home—particularly in the winter months when houses are sealed tight. During heating season, the natural airflow of a home draws crawl space air directly into your upstairs living space (what’s known as the “stack” effect). In fact, about 50 percent of the air you breathe in your home is said to originate from the basement or crawl space. A properly cared-for crawl space can help maintain your home’s structure.
What lies beneath
So, what are the issues you need to ferret out? Moisture, for one. It’s a major contributor to mildew, fungi, and mold, which has been blamed for everything from rashes and runny noses to severe asthma and liver problems. Moisture is also a magnet for spiders, snakes, termites and other nasty pests. Radon is another problem that can originate in dirt or gravel crawl spaces. You can’t see or smell radon—it’s an odorless, colorless gas—but it has major health implications: it’s said to be the number one cause of lung cancer among non-smokers, according to the EPA.
Fortunately, there are relatively simple ways to identify and mitigate these serious health risks. Moisture and mold are commonly spotted with a quick visual inspection or through a “sniff” test: a damp, musty smell is a good sign that there’s excess moisture lurking about. And while radon itself is invisible, radon test kits can uncover the problem. They are widely available, and easy to use. Once you’ve pinpointed the problems, the best first step is to encapsulate your crawl space with a durable, puncture-resistant wall liner that will act as a barrier to insects, gases and odors. You can also help the problem by including a drainage system (a sump pump and a drain tile system) that will redirect any water or moisture that does make its way in. A good last step is spray foam, which minimizes moisture and acts as a nice energy-saver. These are projects an avid DIYer can take on. But, if the idea overwhelms you, there are many professional companiesthat can provide you with a permanent solution—particularly if your problem is radon … that’s something best left to the experts.
What not to do
Regardless of who does the work, there are a couple of things you’ll want to make sure NOT to do. Pumping in concrete, for instance, is an all-around bad idea. That’s because the process introduces hundreds of gallons of water that will ultimately soak into your floor joists and add to the already high humidity levels in your crawl space. Also, pumped concrete floors are different than basement floors; they are chalky and dusty and can introduce more chemicals into the air. Another no-no: spraying closed-cell foam in the crawl space. Spray foam is commonly sprayed at the point where the foundation meets the floor joists. Sealing this joint with a closed-cell material will cause wood rot and severe damage to your home’s structure. Be sure that you use an “open-cell” or “open-weave” type of insulation. No one really wants to think about what lurks in the underworld of a house. But taking a few simple steps to identify and mitigate the problems can protect your family and transform your crawl space into a safe, dry and critter-free area of your home.