Many newer Cincinnati homes have a passive radon vent pipe stubbed into the slab. Activating it (adding a fan) is the cheapest path to mitigation, $700-$1,200 typically. Sump pumps similarly can be sealed and integrated into the system.
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Ohio adopted residential code amendments incorporating radon-resistant new-construction (RRNC) provisions for designated Zone 1 counties around 2009-2010 under OBC 2009, so post-2010 homes in Hamilton, Butler, Warren, and Clermont commonly have a passive 4-inch PVC vent stack stubbed through the slab and routed up through the home, sometimes terminated above the roofline. "Passive" means no fan; the stack relies on stack effect alone, which in Cincinnati climate moves enough air to drop levels modestly but rarely to bring them below 4.0 pCi/L. Activating one (adding an inline fan to the existing stack, sealing the slab penetration, wiring to a dedicated circuit, mounting a manometer) is a 3-4 hour job, $700-$1,200 fixed. Sump pits are similarly an opportunity: a sealed sump pit lid with a gasketed pipe penetration becomes part of the suction network. The on-site assessment identifies which feature exists and writes the quote against that scope. Cincinnati post-2010 construction note: most Mason, West Chester, Liberty Township, and Loveland subdivisions built since 2012 include passive radon stacks per Ohio RRNC code. The stacks are commonly stubbed in a closet or utility-room chase and capped or visibly running through a finished surface. Activation requires a credentialed mitigator because the existing stack diameter and routing may need modification to support an active fan; do not just connect a fan to the stub.