Is white mold on wood in a crawl space dangerous?

Monday, August 26, 2019

White mold in a crawl space indicates elevated humidity, from wet ground, lack of enough ventilation, or both. The good news is that it does not cause structural damage to wood. But white mold will be followed by wood-decay fungi (wood rot) if the moisture level stays high for long enough in the crawl space, and that does destroy wood.

    Also, white mold produces spores as part of its life cycle that can cause hay-fever-like symptoms, asthma, or other allergies. Houses have a natural ground suction action called the “stack effect” and, because no elevated floor is perfectly sealed, a certain amount of crawl space air is drawn into the house every day. It’s unavoidable but, if the crawl space is filled with mold spores, you are going to elevate the spore count inside your home.

    The are numerous natural and chemical biocides that will kill the mold. Then you need to reduce the moisture level in the crawl space so it doesn’t come back, and the culprit is usually lack of sufficient number of vents in the stem wall. It’s dirty work and you may want to hire a professional to do it right.

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Here’s links to a collection of our other blog posts about MOLD, LEAD AND OTHER CONTAMINANTS:

• Is mold contagious? Can mold spread to my home if there is a nearby house with mold?

 Should I buy a house with mold?  

 Why do new homes have more moisture and mold problems than older houses?

 Can infrared thermal imaging find mold behind a wall?

 What is the right humidity level in a mobile home?

 Who can clean up mold found during a home inspection in Florida?

 How do I look for and find mold in my mobile home? 

 Does bleach kill mold?

 Why is there mold around the air conditioning vents? 

 What can I do to prevent mold problems in my home?

 Why is there a lead paint disclaimer in my real estate sales contract? 

 How can I tell if there is asbestos in a house?

 How can I prevent mold in my Florida winter home when I'm gone for the summer? 

 Should I use bleach to clean up mold?

 There's an old fuel oil tank underground in the yard. Is it a problem?

 What are those powdery white areas on my brick walls?

• What should I do if mold is found during a home inspection?

• A neiighbor told me that the house I want to buy once had a bad mold problem. It was not in the seller's disclosure. What should I do? 

     Visit our MOLD, LEAD AND OTHER CONTAMINANTS page for other related blog posts on this subject, or go to the INDEX for a complete listing of all our articles.

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