Harrison County (county seat: Cadiz) covers 404 square miles with a population of 14,483 (2020). Official county website: www.harrisoncountyohio.gov. This page summarizes the verified building-regulation posture of unincorporated Harrison County land; the full 10-dimension scorecard with every source receipt lives on its Freedom Map card.
No certified county residential building dept (county departments list an Engineer, Health Dept and a CIC-run Zoning function, not a building dept); RCO unenforced for new houses in unincorporated Harrison. BUT more township zoning than the batch: five jurisdictions have zoning. County Engineer issues driveway/ROW permits; Health Dept issues septic. [PARAPHRASE + direct quote]
The claim above is source-verified (official statute/county documents; URL, direct quote, and date on the full card). Method: how we verify.
No county's freedom erases state law: septic/wastewater permitting (health authority), well permits and water rights (state engineer/DNR), floodplain rules with federally connected financing, and — in some states — state-run electrical inspections. The full card details which of these bite in Harrison County and how hard.
The score describes unincorporated county land only. Inside Harrison County, incorporated municipalities set their own, usually stricter, rules — including: Cadiz (village, seat), Archer Township, Freeport Township, Moorefield Township, North Township. Land inside town limits follows town code.
Building rules are the first question people ask about Harrison County — and the easiest one to answer. They're rarely the one that decides it. The full card grades all ten dimensions, every claim quoted from the county's own code.
What the Harrison County card answers that this page doesn't:
It's a real map. Click any county in the country and see how it grades — that part costs nothing, and you can compare Harrison County against its neighbors before you spend a dollar.
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Last verified July 2026 · Not legal advice — confirm current rules with the county, the state, and a professional before buying or building.