As I mentioned before in a post about Fixing Plywood Flooring in a Basement, the existence of a plywood floor could simply be because of an uneven floor during construction. The other ugly truth is that this could be an easy and cost effective cover up for what the floor actually is.
Dirt floors in basements and crawlspaces across America are covered up every day with plywood to finally have a solid flat surface for storage. The problem with having a dirt floor is now moisture has a direct path into the basement, not to mention Soil Gases like Radon, Insects and other nasty business.
With open dirt floors in a tight space like a crawl space or basement the levels of moisture can sky-rocket and eventually cause large issues.
The wood that would keep your things steady and dry could become the food for mold and mildew and turn against the homeowner.
If a crawlspace has a dirt floor the best solution would be to encapsulate the crawlspace. This not only keeps the moisture out, it also improves the air quality and protects the insulation underneath the 1st floor of the home.
Related Reading and Links
Read about the Top 6 Basement Mistakes that contractors and homeowners make.
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