A bill in the Illinois legislature would require all new residential construction to have passive radon resistant construction, which can be activated if levels are found to be too high. Radon removal involves collecting soil gas from below the foundation and piping it to a safe location outside above the roof. A passive radon system in a new home would cost $300 to $500, compared to mitigation costs of $1,200 to $1,500 after a house is built.
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