ADU Pass
Erie County
ADU Pass helps homeowners in Erie County, Ohio navigate the permit paperwork for building an accessory dwelling unit. We cover 7 cities and 7 ZIP codes in this county.
Map
County ADU details
County ADU ordinance
Erie County, Ohio (Lake Erie shoreline tourism county; ~75,300 residents; county seat Sandusky; home of Cedar Point amusement park; 14 townships including Berlin, Florence, Groton, Huron, Kelleys Island, Margaretta, Milan, Oxford, Perkins, and Vermilion townships; incorporated places City of Sandusky, City of Huron, City of Vermilion (split with Lorain County), Village of Castalia, Village of Kelleys Island, Village of Milan, Village of Berlin Heights, and Village of Bay View) HAS adopted countywide rural zoning under O.R.C. Chapter 303 (Erie County is one of the minority of Ohio counties that operates county-tier zoning, alongside Lake County, Summit County, Geauga County, and a handful of others). The Erie County Zoning Resolution is administered by the Erie County Regional Planning Commission and the Erie County Building Department; it covers unincorporated parcels in townships that have not adopted their own Chapter 519 township zoning. Several Erie County townships (notably Perkins Township, which surrounds Sandusky and contains the Cedar Point causeway corridor, and Huron Township and Margaretta Township) have adopted their own township zoning resolutions under O.R.C. Chapter 519, which then displace the county resolution within those township boundaries. The Erie County Zoning Resolution does NOT explicitly use the phrase 'accessory dwelling unit' as a separately permitted use; second dwellings on a parcel are evaluated under the resolution's general single-family residential district provisions, which historically permit only one principal dwelling per zoning lot. An attached in-law suite that shares the main structure and lacks a separate utility connection is typically treated as a single dwelling unit, while a detached secondary dwelling generally requires either a lot split, a conditional use approval, or qualification as an agricultural-use exemption under O.R.C. § 303.21 (the Ohio agricultural exemption that immunizes farm-related dwellings on parcels of five or more acres from county zoning when used in connection with bona fide agricultural production).
County assessor
Assessment policy: The Erie County Auditor is the elected property-assessment authority under O.R.C. § 5713.01. Ohio assesses real property at 35% of true value (O.R.C. § 5713.03). New ADU construction is added to the parcel record on the next regular revaluation cycle (Ohio statutorily requires a sexennial reappraisal with a triennial update; Erie County's most recent reappraisal was on the 2023 cycle, with a triennial update due in 2026) and reassessed at true value as of January 1 following completion. The Ohio Owner Occupancy Credit (O.R.C. § 323.151 et seq.) provides a 2.5% reduction in tax on owner-occupied homestead; the Homestead Exemption (O.R.C. § 323.152) reduces taxable value by $25,000 for owners 65+ or totally and permanently disabled, subject to income tests. Erie County also administers Current Agricultural Use Valuation (CAUV) under O.R.C. § 5713.30-§ 5713.38 — significant in the inland southern and western portions of the county (Margaretta, Groton, Florence townships) where commercial row-crop agriculture and orchards (the county is a notable peach- and apple-growing area along the lake-moderated climate band) qualify. An ADU built on a CAUV parcel may trigger a partial recoupment (rollback) if the dwelling reduces the parcel's qualifying agricultural acreage below the CAUV threshold. Under O.R.C. § 5713.17, the owner must notify the Auditor of any construction or improvement valued over $2,000. Erie County also has a high proportion of seasonal / second-home properties along the Lake Erie shoreline and on Kelleys Island; these do not qualify for the Owner Occupancy Credit or Homestead Exemption.
County overlays (6)
Known county issues (5)
- other — ADU construction on shoreline parcels in Erie County faces a regulatory cascade extending beyond county zoning to ODNR coastal management and federal USACE permits. Some shoreline parcels are effectively unbuildable for new permanent structures within the CEA without expensive shoreline-protection engineering.
- other — ADU construction on parcels in the Old Woman Creek watershed faces additional environmental review for stormwater, nutrient loading, and wetland impact beyond the standard Erie County General Health District septic review.
- other — ADU researchers and applicants in Erie County should check the STR ordinance of the host city or village (or, in unincorporated areas, the township) separately from the underlying zoning rule on ADU permissibility. Some jurisdictions permit ADUs but restrict short-term rental of any portion of a residential parcel.
- other — Researchers and applicants must first identify whether the parcel falls inside an incorporated city or village, inside a township with its own zoning, or in territory governed by the Erie County Zoning Resolution. Failing to do this can lead to applying the wrong ordinance entirely.
- policy-review — Researchers should monitor the Ohio General Assembly for any future ADU preemption proposal; until one passes, ADU permissibility in Erie County depends on the specific city, village, township, or county-zoning territory and on the overlay constraints (coastal, floodplain, historic, CAUV).
Federal (United States) — ADU-relevant rules and programs
Federal ADU law
The United States has no federal statute that directly regulates accessory dwelling unit entitlement or design. Land-use authority over ADUs resides with states and local governments under the traditional police power. Federal engagement is limited to financing (Fannie/Freddie/FHA/VA/USDA), flood insurance (FEMA/NFIP), and discretionary housing programs (HUD), which are recorded in sibling sections of this file.
Federal financing programs
Federal housing-finance agencies and GSEs set nationwide underwriting rules that govern whether an ADU can be financed, appraised, and counted toward mortgage qualifying income. The relevant actors are Fannie Mae, Freddie Mac, FHA (HUD), VA, and USDA Rural Development.
Federal tax credits
There is no ADU-specific federal tax credit. ADUs may incidentally qualify for existing federal energy-efficiency and clean-energy tax credits when the ADU construction includes qualifying measures.
Federal housing programs
HUD administers several discretionary programs that can fund ADU-related activity at the grantee's election, but none is an ADU-specific program.