Direct answer
Sub-membrane depressurization is the crawl-space variant of mitigation. Partner-network mitigators install a sealed vapor barrier across the crawl space floor and create suction beneath it to draw radon away. Often combined with encapsulation.
Authoritative sources
Cincinnati and surrounding counties sit in EPA Radon Zone 1, the highest-risk classification.
EPA recommends mitigation above 4.0 pCi/L and consideration of mitigation between 2.0 and 4.0 pCi/L.
Ohio Radon Program guidance on testing, mitigation, and contractor licensure.
Related questions
We connect Greater Cincinnati homeowners with NRPP-credentialed radon mitigators in our partner network. Mon-Sat 8am-7pm.
