Henry County

Permit responsibility in unincorporated Henry County is split across the township zoning inspector network, the state residential building program, the county planning commission's floodplain function, and the county health department. (1) Township zoning permits for residential construction (including ADUs as accessory residential structures, where allowed) are issued by the zoning inspector of the township the parcel sits in. Henry County's zoning-inspector roster (as posted by the Henry County Planning Department) shows each of the thirteen townships with an assigned inspector: Bartlow (Evan Geno), Damascus (Andrew Rehner), Flatrock (Henry County Planning, contract), Freedom (Kim VanValkenburg), Harrison (Laura Bishoff), Liberty (Henry County Planning, contract), Marion (Peter Willhelm), Monroe (Darvin Biederstedt), Napoleon (Henry County Planning, contract), Pleasant (Pete Giesige), Richfield (Evan Geno), Ridgeville (Eric Rohrs), Washington (Brad Meister). The county planning office serves as the zoning inspector under contract for Flatrock, Liberty, and Napoleon Townships. (2) Residential building permits under the Ohio Residential Code (RCO) for one-, two-, and three-family dwellings in unincorporated Henry County are administered through the Ohio Department of Commerce / state residential building program rather than a county-staffed building department; Henry County does not maintain a certified residential building department of its own. (3) Floodplain development permits in unincorporated Henry County are issued by the Henry County Planning Commission, whose director serves as the county floodplain manager. (4) On-site sewage permits (Household Sewage Treatment Systems) are issued by the Henry County Health Department (1843 Oakwood Avenue, Napoleon) under Ohio Administrative Code 3701-29; HSTSs are also entering a five-year operation-and-maintenance permit cycle by township groups (Liberty and Napoleon Townships scheduled for October 2025 to September 2026). (5) Driveway access permits onto county roads are issued by the Henry County Engineer. An ADU project in unincorporated Henry County therefore typically requires: a township zoning permit (where the township has zoning that permits or conditionally permits ADUs), a state-program residential building permit, a county floodplain development permit if the parcel is in a FEMA SFHA (the Maumee River corridor through the county is the main one), an HSTS install permit and operation permit where no public sewer is available, an engineer driveway permit if applicable, and an address assignment.

Process overview: Typical Henry County unincorporated ADU workflow: (1) Identify the township the parcel sits in and contact that township's zoning inspector (Flatrock, Liberty, and Napoleon Townships use the county planning office as their inspector under contract; the other ten townships have independent inspectors). (2) Confirm the parcel's zoning district, whether ADUs or accessory residential structures are permitted, conditional, or prohibited, and obtain a township zoning permit. (3) Apply for a residential building permit under the Ohio Residential Code through the Ohio Department of Commerce state residential building program (Henry County does not operate its own certified residential building department). (4) Submit a floodplain development permit application to the Henry County Planning Commission if the parcel is in a FEMA Special Flood Hazard Area - the Maumee River corridor through Napoleon and the upstream and downstream townships is the primary mapped flood zone (roughly 3.2-3.75 percent of total county acreage, about 8,624-10,000 acres, sits in the 100-year floodplain per the 2024 Henry County Hazard Mitigation Plan). (5) Apply for an HSTS install permit through the Henry County Health Department if the parcel is not on public sewer, and expect to receive a five-year HSTS operation permit on the township's rotation schedule. (6) Apply for a driveway access permit through the Henry County Engineer if access is from a county road. (7) Receive an address assignment. (8) Construct with required inspections; receive Certificate of Occupancy from the building official of record (typically the state RCO program).

Impact fees: Henry County itself does not levy a county impact fee on residential construction. Fees paid on an unincorporated ADU project are itemized by issuing authority: the township zoning permit fee (set by each township, typically a flat residential fee in the $25-$150 range), the Ohio Residential Code permit fee under the state RCO program, the Henry County Planning Commission floodplain development permit fee if applicable, an HSTS install permit fee from the Henry County Health Department plus the five-year HSTS operation permit fee under the county's 2023 O&M regulation, and an engineer driveway access permit fee where applicable. Confirm all current fee schedules with the issuing office at intake.

The Henry County Auditor (Elizabeth Fruchey; 660 N Perry Street, 2nd Floor Courthouse, Napoleon OH 43545; 419-592-1956) is the elected county official responsible for valuing all real property in Henry County for property-tax purposes, including new ADU improvements added to a host parcel. Henry County follows the Ohio Department of Taxation's mandated valuation cycle: a sexennial (six-year) full reappraisal and a triennial (three-year) update between reappraisals. New ADU square footage and exterior changes are picked up either through the building-permit feed from the building department of record (state RCO program for unincorporated areas, or the municipal building department for parcels inside Napoleon or one of the incorporated villages) or through the Auditor's field-canvass during reappraisals. Ohio's owner-occupancy 2.5% reduction (ORC 323.152) and the Homestead Exemption (for qualifying senior, disabled, or surviving-spouse owner-occupants) apply to the principal residence on the parcel but do not exempt the value added by new ADU improvements. An ADU built and rented (not owner-occupied) does not by itself revoke the principal-residence owner-occupancy reduction on the rest of the parcel, but converting the principal residence itself to a rental does. Henry County is heavily agricultural, so a large share of unincorporated parcels are enrolled in Current Agricultural Use Value (CAUV) under ORC Chapter 5713; the Auditor administers CAUV enrollment, valuation, and the recoupment of three prior years' tax savings if a CAUV parcel comes out of agricultural use. Valuation disputes are heard by the Henry County Board of Revision under ORC Chapter 5715. Parcel data is available through the county's online parcel-search portal (Appraisal Research Corp).

Assessment policy: Sexennial full reappraisal and triennial update cycle, mandated statewide by the Ohio Department of Taxation. New ADU improvement value is added to the parcel's improvement value on the next valuation cycle following construction, picked up via building-permit data from the state RCO program or the relevant municipal building department and through field canvass. Owner-occupancy 2.5% reduction (ORC 323.152) and Homestead Exemption attach to the principal residence on the parcel and reduce tax owed on that portion but do not exempt the added ADU improvement value. CAUV (ORC 5713) is heavily used in Henry County given its agricultural base; ADU construction on a CAUV parcel can trigger partial removal from CAUV for the expanded homesite area with three years of recoupment under ORC 5713.34. Valuation challenges go to the Henry County Board of Revision under ORC Chapter 5715.

Henry County's dominant cross-county overlay is FEMA NFIP floodplain regulation along the Maumee River corridor, which bisects the county roughly west-to-east through Damascus, Napoleon, Flatrock, and Washington Townships and through the City of Napoleon. The 2024 Henry County Hazard Mitigation Plan reports that roughly 3.2 to 3.75 percent of the county's total acreage - about 8,624 to 10,000 acres - sits in the 100-year floodplain or flood hazard area. The county participates in the National Flood Insurance Program and the Henry County Planning Commission director serves as the county floodplain manager, issuing floodplain development permits for unincorporated SFHA parcels and coordinating with the City of Napoleon and the villages on their municipal NFIP compliance. There is no countywide coastal overlay (Henry is inland), no wildland-urban-interface fire overlay, and no countywide historic-preservation overlay. The second large operational overlay is agricultural-use enrollment under CAUV (ORC 5713), which covers a substantial share of unincorporated parcels given Henry County's predominantly-agricultural land use - any ADU on a CAUV parcel needs to address the homesite-area expansion and three-year recoupment exposure with the Auditor. A third county-wide regulatory feature, distinct from a zoning overlay but operationally significant for any new dwelling, is the Henry County Health Department's five-year HSTS Operation and Maintenance Program adopted in spring 2023, which is being phased in by township groups (Liberty and Napoleon Townships scheduled October 2025 to September 2026); any ADU using a new or existing septic system will be in scope.

• FEMA NFIP Special Flood Hazard Areas along the Maumee River corridor in Henry County — Critical facilities must be sited outside the SFHA when feasible. Letter of Map Amendment (LOMA) and Letter of Map Revision (LOMR) processes can adjust effective mapping for parcels with verified higher ground elevations. The Henry County Engineer maintains downloadable FEMA 100-year flood GIS layers on request.
• Agricultural-use parcels under CAUV (Current Agricultural Use Value) — ADU applicants on CAUV-enrolled parcels should consult the Henry County Auditor (419-592-1956) before construction to confirm homesite-area treatment and quantify recoupment exposure.
• Henry County HSTS Operation and Maintenance Program (five-year septic operation permits) — ADUs on parcels with public sewer (primarily inside the City of Napoleon and certain villages) are not subject to the HSTS program. The county maintains a list of approved STS service providers.