Of all the things that may be living in a crawl space, mold is potentially the most dangerous. Mold stinks. It can cause a host of health problems. It damages wood framing and floors. It is difficult and expensive to get rid of.
Types Of Crawl Space Mold
The three most common molds to appear in crawl spaces are white, yellow, and black.
- White Mold. Appears soft and fuzzy. Sprouts on exposed moist soil. Has an affinity for exposed crawl space joists.
- Yellow Mold. Appears smooth and flat. Causes most damage to wood framing. May turn gray with age.
- Black Mold. Most toxic because it has the highest level of mycotoxins. Sometimes appears greenish in color. Starts by growing in clusters but will colonize entire areas over time.
Dangers Of Mold In Crawl Spaces
Mold flourishes in warm damp locations that contain organic food sources like wood, cardboard, and dust. There are thousands of types of mold fungi–over 1000 reside in the US. Most of them are fairly benign. Some are extremely dangerous.
Health Dangers
Up to 60% of crawl space air flows into living areas through gaps, cracks, floor penetrations, and HVAC systems. Carrying mold spores with the potential for health problems. Not everyone is allergic to mold, but for those that are, it causes cold and flu-like symptoms.
- Coughing.
- Sneezing.
- Runny Nose.
- Sore Throat.
- Runny Eyes.
- Rash. Skin Irritation.
- Asthma Attacks.
The symptoms range from mild to severe. If they are continuous or recurring, the cause could be mold sensitivity. Intermittent symptoms point to a cold, flu, or existing asthma.
Some people can suffer from Toxic Mold Syndrome. The symptoms include:
- Depression.
- Memory Loss.
- Anxiety.
- Confusion.
- Loss of Appetite.
Toxic Mold Syndrome is associated with black mold. It is blamed for causing deaths, but there are some questions about that assertion.
Structural Dangers
Crawl spaces provide plenty of food sources for mold. Floor joists, the underside of floor plywood, dust, and anything organic stored in them like cardboard, books, and fabric.
Undetected and untreated mold grows out of control and eventually rots framing. Floors can become rotted and spongy. If left long enough, mold leads to the need for structural repair.
Mold spores moving from the crawl space into the home’s living areas increase the chances of mold growth in bathrooms and kitchens.
Causes Of Mold In Crawl Spaces
Mold spores are everywhere. They blow into crawl spaces through vents and other openings. Once inside they grow if moisture is present–condensation, groundwater, plumbing leaks, etc.–on the abundant food sources.
Many homeowners rarely–or never–enter their crawl spaces. (Some people do not even realize a crawl space exists under the house.) Mold growth can become extensive over time. Removing large mold infestations is time-consuming and expensive.
Preventing Mold In Crawl Spaces
Encapsulating crawl spaces is the best way to prevent mold growth. Mold only grows when moisture is present. Encapsulation is designed to eliminate moisture. A second option is to insulate the crawl space and provide sufficient ventilation.
All mold must be removed before the preventative work is done. Given the right conditions, mold continues to grow behind encapsulation. Covered mold can’t be seen. It spreads and causes damage unhindered.
DIY prevention includes regular inspection, removing all mold, and sanitizing the area. Mold is dangerous. Wear personal protective equipment including a hazmat-type coverall c/w hood, gloves, footwear that can be cleaned, and a respirator with HEPA filter.
Large infestations and repairs to framing are best left to professional mold removal specialists. They cost more than DIY mold removal but are in and out quickly, protect the occupants, and usually offer a warranty.
