Chicago and the surrounding suburbs have some of the highest radon levels in the country. A concrete floor in the crawlspace will mitigate the problem in your home. The American Lung Assocation and The E.P.A (Environmental Protection Agency) recommend a concrete floor and proper drainage be installed in all existing crawlspaces.

How radon gets in to your home: Unfinished crawlspace Construction joints Cracks in walls Gaps in suspended floors Gaps around service pipes Cavities inside walls Cracks in solid floors