Off-Grid Living in Miami County, Ohio

Miami County, Ohio is a tricky one to give a simple answer on, because there isn't one countywide rulebook. I've dug through the official pages, and here's the honest picture.

Zoning depends entirely on where you land. The Miami County Department of Development administers zoning for eight of the twelve townships (Concord, Monroe, Newberry, Newton, Springcreek, Staunton, Union, and Washington) under the county zoning resolution, itself authorized by state law (ORC Chapter 303). But Bethel, Brown, Elizabeth, and Lostcreek townships run their own separate zoning, and incorporated places like Troy, Piqua, and Tipp City have their own city zoning and building departments entirely. Before you buy or plan anything, I'd call to confirm exactly which authority governs your specific parcel.

Dwellings and tiny homes/RVs aren't spelled out clearly on the county's public pages. Ohio's statewide manufactured-home protections would apply as a baseline, but any local size or density rules for tiny homes or RV-as-residence setups aren't confirmed at the county level, so ask the Department of Development or your township directly. Also worth noting: private deed restrictions and covenants can add rules on top of zoning, and a zoning permit doesn't override those.

Building permits are required for unincorporated areas under county jurisdiction, enforced by the county's Building Regulations division using the statewide Residential Code of Ohio and Ohio Building Code (plus Ohio Mechanical Code updates). The county has its own local submittal process, like requiring plans as a single multipage PDF, so check with them before submitting anything.

Septic systems are permitted through Miami County Public Health, which handles site evaluation, design approval, installation inspection, and an ongoing Operation & Maintenance program, this last part required statewide under Ohio Administrative Code 3701-29-09(I). Composting toilets aren't separately addressed on the county's page, so I'd treat them as falling under that same state sewage framework and confirm directly with Environmental Health.

Greywater and rainwater harvesting have no dedicated Miami County page that I could find. Both would presumably fall under the state's OAC frameworks administered locally by the health district, but the exact local procedure isn't confirmed, so this is a call-and-ask situation.

Private wells are permitted with a permit through Miami County Public Health, consistent with statewide rules. If your parcel happens to be within the small service areas of Bethel, Concord, Monroe, or Springcreek townships, county Sanitary Engineering may run water/sewer infrastructure there instead, but that's the exception, not the rule.

Full utility disconnection isn't explicitly addressed by any ordinance I found, mandating or prohibiting it. Outside the sanitary sewer service townships, private well and septic are just the default setup, not a special "off-grid" category, and you'd still need to meet building code and health permitting either way.