Bolthole Index

Union County, Ohio

Building permits, zoning and septic rules in Union County, Ohio

41Index Score / 100
#70 of 88 in Ohio

Union County, Ohio requires building permits in the areas served by the Union County Building Department, but Dublin and incorporated Plain City use other building departments12. Zoning approval does not come from the county: the individual township or municipality sets zoning, and Jackson Township is the one township without a zoning-permit requirement34. Septic permits for land beyond public sewer come from the Union County Health Department5.

At a glance

Building permit
Required in the Union County Building Department's service area, with limited exemptions1
Zoning
Township or municipal rules apply; permits are required in most municipalities and every township except Jackson Township4
Septic permits
Installation and operating permits from the Union County Health Department6
Owner-builder exemption
No general permit exemption; owners must obtain plan approval before construction7
Agricultural building exemption
Conditional on the township zoning inspector determining that the use is agricultural8
Minimum home size and setbacks
Set by the applicable township or municipality, not by one countywide standard910
Private well
Health Department permit and site inspection before issuance11

Who to call

Building permits

Union County Building Department (Engineer's Office, Building Regulation)

Building permits, plan review and inspections for construction in Union County; zoning approval must be obtained separately from the applicable township or municipality

937-645-3018

engineer@unioncountyohio.gov

233 West 6th Street, Marysville, OH 43040

Health department

Union County Health Department (Environmental Health)

Household sewage treatment system (septic) installation permits, operating permits and inspections for Union County

937-642-2053

ehcontact@uchd.net

940 London Avenue, Suite 1100, Marysville, Ohio 43040

Contact details are copied from each office’s official page and were checked against it on October 9, 2026.

Off-grid gear

Going off-grid in Union County means bringing your own water and power. The kit we’d start with:

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Do you need a building permit in Union County, Ohio?

Yes. Building permits are required for construction in areas served by the Union County Building Department, and plumbing, electrical and mechanical work also requires permits1. The county does not provide building-code enforcement in Unionville Center, incorporated Plain City or the City of Dublin; Dublin has its own building department, while the West Jefferson Building Department handles incorporated Plain City2. Small residential sheds of 200 square feet or less and commercial sheds of 120 square feet or less are exempt, and patios do not require a building permit, although zoning approval may still apply1. An owner-builder does not receive a general exemption from plan approval: the owner must submit plans to the building department with jurisdiction and wait for approval before starting12. An agricultural building qualifies for the building-code exemption only after the township zoning inspector determines that its use is agricultural rather than residential accessory or commercial storage; a later residential or commercial conversion requires change-of-occupancy approval and compliance with the new use's code requirements8.

Who issues building permits in Union County, Ohio, and how do you reach them?

The Union County Building Department reviews construction documents and issues permits in its service area from 233 West 6th Street in Marysville13. Applicants submit the online application with drawings and specifications, then secure plan approval, local zoning approval, any required Health Department approval and payment of fees14. Applications with construction drawings must be reviewed within 30 days, while permits without drawings are typically issued within 1 week14. The residential fee schedule charges a $35 application fee and a $105 plan-review fee for a new building, addition or accessory building, both due when the application is submitted, with the permit fee based on square footage plus a 1% Ohio surcharge15. Inspections are mandatory for work constructing, altering or adding to one-, two- and three-family residences16. A regulated building cannot be used or occupied until required inspections are complete and the building official issues a Certificate of Occupancy17.

Does Union County, Ohio have zoning, and who administers it?

Union County does not administer a countywide zoning ordinance: zoning authority has been voted to the individual townships, with municipal zoning inside cities and villages3. Zoning permits are required in most municipalities and all townships except Jackson Township4. Minimum road frontage, setbacks and minimum square feet per household vary with the local district4910. A parcel's mailing address alone therefore does not answer what can be built: identify the governing township or municipality and ask its zoning official whether the intended use is allowed before commissioning plans. Jackson Township's zoning-permit exception does not erase applicable building, septic, well, driveway or floodplain requirements416111819. Union County's building workflow treats local zoning approval as a separate prerequisite where required14.

How do septic permits work in Union County?

Where public sewage service is unavailable, Union County allows an on-site household sewage treatment system, but the site must also reserve space for a backup system20. Before installation, submit the site and design application, house plan, soil report from a registered soil scientist, and applications for both installation and operating permits to the Union County Health Department6. The installer must arrange an inspection before backfilling, and the Health Department returns 12 months after a new system is completed; later operation-and-maintenance inspections depend on system type21. Only about 0.1% of Union County soils are rated without severe limits for a conventional drain field, so settle septic feasibility before choosing a house location22. Site-specific soil, water table, bedrock, slope and floodplain conditions can constrain the approved design20.

Can you live in an RV or tiny home on your land in Union County?

We could not confirm a countywide rule allowing an RV or tiny home as a residence on private land. The applicable township or municipality controls zoning, including district-specific setbacks and minimum square feet per household, so ask that zoning official about the proposed unit and occupancy before buying4910. A tiny home used as a dwelling still faces the applicable building-permit process in the Union County Building Department's service area1. An off-grid plan also needs an approved septic system where public sewage service is unavailable, and a private well requires a Health Department permit and a site inspection before permit issuance2011. A manufactured home generally cannot be occupied until the state inspector issues its inspection seal, apart from the temporary-occupancy exception23.

How do you build a home in Union County, Ohio, step by step?

  1. Identify the township or municipality and confirm permitted use, minimum dwelling size, frontage and setbacks with its zoning official4910.
  2. Confirm whether the Union County Building Department or an alternative authority serves the parcel2.
  3. If public sewer is unavailable, obtain a soil report and complete the Health Department's septic site-and-design process6.
  4. Apply to the Health Department for a private-well permit and complete the required site inspection before permit issuance11.
  5. Obtain a driveway permit from the Union County Engineer for a county or township road, or contact the Ohio Department of Transportation for a state highway18.
  6. If the home site is in a flood hazard area, obtain the county permit for unincorporated land; check with local officials inside a municipality19.
  7. Submit the building application and drawings, secure approvals, pay the fees, and wait for issuance before work begins141.
  8. Complete required inspections and obtain the Certificate of Occupancy before using the building1617.

What should you check before buying land in Union County?

Confirm septic capacity, water, legal access, floodplain status and any planned land split before closing. Only about 0.1% of Union County soils are rated without severe limits for a conventional drain field, and the Health Department requires a soil report for the septic application226. A private well needs a permit and a site inspection before permit issuance11. The County Engineer permits new driveways on county and township roads; the Ohio Department of Transportation handles state-highway access18. A home planned within a flood hazard area in unincorporated Union County needs a flood hazard area permit; inside a municipality, ask city or village officials19. In unincorporated Union County, selling or subdividing part of a property must follow the Union County Subdivision Regulations, and the County Engineer reviews the plats2425. Verify the local zoning district because setbacks, frontage and dwelling size vary4.

Watch-outs

  • Zoning requirements vary by township and municipality; Jackson Township is the township exception to the local zoning-permit requirement4.
  • Only about 0.1% of Union County's soils are rated free of severe limits for a conventional septic drain field, so do not assume a standard gravity septic system will work without a site evaluation22.
  • A permit or plan approval becomes invalid if work has not started within 12 months, or is delayed more than 6 months once started, so plan your construction schedule around those deadlines13.

Sources

  1. Ready, Set, Build!, quoted and re-checked
  2. Building Dept FAQ, quoted and re-checked
  3. Union County Board of County Commissioners, quoted and re-checked
  4. Ready, Set, Build!, quoted and re-checked
  5. Septic Systems, quoted and re-checked
  6. Septic Systems, quoted and re-checked
  7. Section 3791.04 | Submission of plan - approvals - prohibition - fine (2026 county census)
  8. Building Dept FAQ, quoted and re-checked
  9. Ready, Set, Build!, quoted and re-checked
  10. Ready, Set, Build!, quoted and re-checked
  11. unioncountyohio.gov, quoted and re-checked
  12. Section 3791.04 | Submission of plan - approvals - prohibition - fine (Ohio statewide rule), quoted and re-checked
  13. Union County Building Department (Engineer's Office, Building Regulation) (unioncountyohio.gov)
  14. Building Dept FAQ, quoted and re-checked
  15. Residential Information, quoted and re-checked
  16. Residential Inspection Requirements, quoted and re-checked
  17. Application for Certificate of Occupancy, quoted and re-checked
  18. unioncountyohio.gov, quoted and re-checked
  19. Ready, Set, Build!, quoted and re-checked
  20. Septic Systems, quoted and re-checked
  21. Septic Systems, quoted and re-checked
  22. Share of soils USDA rates "not limited" for a conventional septic drain field (SSURGO). A strict rating: the median county is about 6% and a tenth of counties are 0%, so a low figure means most lots need a site evaluation or an engineered system, not that septic is impossible. Cite it only with that caveat: Bolthole Index county data
  23. Chapter 4781-7 | Manufactured home inspections (Ohio statewide rule), quoted and re-checked
  24. unioncountyohio.gov, quoted and re-checked
  25. unioncountyohio.gov, quoted and re-checked

Written October 9, 2026 from the rules quoted below, each taken from an official source and re-checked by an independent reviewer. This is research, not legal advice: rules change, so confirm with the office before you buy or build.

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Compared with neighboring counties

Unlike 5 of its 6 neighbors, Union County has no countywide zoning.

RuleUnion CountyMarion CountyLogan CountyDelaware CountyChampaign CountyHardin CountyMadison County
Building permitRequiredLimitedRequiredRequiredRequiredLimitedRequired
County zoningNoYesYesYesNoYesYes
Septic permitsCounty Health Dept.Marion Public HealthCounty Health DistrictDelaware Public Health DistrictChampaign Health DistrictKenton-Hardin Health Dept.County Public Health

County locator

Union County in Ohio

41
County map
Union County highlighted among the Ohio counties · colored by Index score

How Union County scores

Seclusion18100% ev.
Self-Sufficiency44100% ev.
Admin Boringness4290% ev.
Durability82100% ev.
Property Autonomy35100% ev.
Carry Cost62100% ev.

Evidence strength: 98%. This reports direct-source completeness and fallback use; it is separate from the score and is not a confidence interval. How it works →

$419kTypical home
1.3%Property tax
$8,151Land / acre
39.4"Annual rain
0.8% of yrsSevere drought
3.7 / yr (+3.7)Mid-century 100°F days
12.1 daysMid-century dry spell
1.59" (+8.9%)Mid-century 1-day rain
1.86×Wildfire change factor
100%Forward climate coverage
$1,469Home insurance / yr
1.5% / yrInsurance growth
1.33%Nonrenewal rate
county median (2+ published ZIPs)Insurance basis
89,000People within 30 min
6,238,746People within 2 hr
133,992Radius comparison (15 mi)
161.3People / sq mi
0.2%Federal land
99.9%Land at 15% slope or less
0.1%Soils rated "not limited" for septic (strict USDA rating)
379 acWorkable land screen
12.9%Wooded land
26.6 tonsBiomass / forest ac
51.6°FAvg temp

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Cities and towns in Union County

Inside a city, town or township here, that government usually sets zoning and may issue its own building permits; the county’s rules above cover land outside them.

Not yet researched: Allen Township · Claibourne Township · Darby Township · Dover Township · Jackson Township · Jerome Township · Liberty Township · Village of Magnetic Springs · Village of Milford Center · Millcreek Township · Paris Township · Taylor Township · Union Township · Village of Unionville Center · Washington Township · Washington Township · York Township

Answers from the rulebook for Union County

What the ordinances and state agencies actually say — one answer per question, each quoted from the official source and independently re-checked.

Union County rules

  • Building permitRequired

    Building construction in Union County, subject to listed permit exemptions

    • Only work not requiring a permit or emergency repairs may proceed without a permit.
    • Construction work may begin after the permit is issued.
    • Agricultural buildings may be exempt when the township zoning inspector determines the use is agricultural under ORC 3781.061.
    • Residential sheds of 200 square feet or less and commercial sheds of 120 square feet or less are exempt; zoning permits may still be required.
    • Decks meeting all listed RCO 102.1 conditions are exempt; patios do not require a building permit but may require zoning approval.
    “Building permits are required in Union County. Contact our office for building permit information. Plumbing, electrical, and mechanical permits are also required.”
    2 more reviewed findings on this topic
    • Required — Building construction in Union County areas served by the Union County Building Department.
      “Building permits are required in Union County. Contact our office for building permit information. Plumbing, electrical, and mechanical permits are also required.”
    • Required — Building construction in Union County subject to the county building-permit program.
      “Building permits are required in Union County. Contact our office for building permit information. Plumbing, electrical, and mechanical permits are also required.”
  • Building code adoptedAdopted (with conditions)

    Building-code enforcement performed by the Union County Building Department

    • Union County has agreements with municipalities for enforcement except Unionville Center, incorporated Plain City, and the City of Dublin.
    • Dublin is the regulatory authority within incorporated Dublin; West Jefferson Building Department is the permitting authority inside incorporated Plain City.
    “The Union County Building Department will review construction documents ensuring the proposed work conforms to the adopted building codes.”
    2 more reviewed findings on this topic
    • Adopted (with conditions) — Construction reviewed by the Union County Building Department in its service area.
      “The Union County Building Department will review construction documents ensuring the proposed work conforms to the adopted building codes.”
    • Adopted (with conditions) — Construction subject to Union County Building Department enforcement agreements.
      “The Union County Building Department will review construction documents ensuring the proposed work conforms to the adopted building codes.”
  • InspectionsRequired

    Improvements constructing, altering, or adding to one-, two-, and three-family residences handled by the Union County Building Department.

    • Job-specific inspections may also be required.
    • Approved plans and documents must be onsite.
    • Plumbing permits and inspections are issued and performed by the Union County Health Department.
    • A reinspection fee may be charged for noncomplying or incomplete work.
    “Inspections of improvements made in constructing, altering, or adding to one, two and three family residences are mandatory.”
  • Certificate of occupancyRequired

    Buildings regulated by the Union County Building Department before use or occupancy.

    • No building or structure may be used or occupied until the building official issues approval in the form of a Certificate of Occupancy.
    • The certificate states the conditions of use, and the owner must comply with them.
    • For an existing building, the application is unavailable when there is a proposed change of occupancy, alteration, or addition.
    • All required inspections must be completed before issuance.
    • A 3% state surcharge, application fee, and Certificate of Occupancy fee apply to the existing-building application.

    state surcharge: 3 percent

    “Section 111.1 Ohio Building Code states that no building or structure, in whole or in part, shall be used or occupied until the building official has issued an approval in the form of a Certificate of Occupancy.”
  • County-wide zoningAbsent (with conditions)

    County zoning authority in the unincorporated area of Union County.

    • Zoning authority has been assigned to individual townships rather than administered as a countywide zoning ordinance.
    • Municipal zoning may apply inside incorporated cities and villages.
    “The Ohio General Assembly delegated to the county commissioners the power to administer zoning laws for the unincorporated areas of the county in 1947. In Union County zoning authority has been voted to the jurisdiction of the individual townships, who establish rural zoning commissions and a boards of zoning appeals.”
  • Local zoningVaries (with conditions)

    The aggregate local-zoning landscape across Union County townships and municipalities.

    • The county guide states zoning permits are required in most municipalities and all townships except Jackson Township.
    • Each township and municipality has its own requirements.
    • The county's local-codes page identifies ordinances of political subdivisions located in Union County and links to municipal codes.
    • The conclusion aggregates township and municipal zoning; it does not claim that Union County administers every local zoning ordinance.
    “Zoning permits are required in most municipalities in Union County and in all townships in Union County except for Jackson Township.”
    One more reviewed finding on this topic
    • Varies (with conditions) — Aggregate of zoning controls administered by Union County townships and municipalities
      “Contact the appropriate township or municipal zoning official to determine if the land is properly zoned for your intended use. Each township and municipality has its own requirements such as minimum road frontages, setbacks, and square feet per household.”
  • Minimum dwelling sizeDistrict specific (with conditions)

    Local township and municipal zoning requirements affecting minimum square feet per household.

    • Requirements vary by township and municipality.
    • The county guide does not provide the numeric minimums; the applicable local zoning official must be consulted.
    “Each township and municipality has its own requirements such as minimum road frontages, setbacks, and square feet per household.”
    One more reviewed finding on this topic
    • District specific (with conditions) — Minimum dwelling-size or square-foot requirements imposed by applicable township or municipal zoning authorities.
      “Each township and municipality has its own requirements such as minimum road frontages, setbacks, and square feet per household.”
  • Minimum lot sizeDistrict specific (with conditions)

    Residential lot-size requirements in Union County, with the underlying requirements administered by individual townships and municipalities rather than by a single countywide zoning rule.

    • The official county guide states that each township and municipality has its own requirements, including minimum road frontages, setbacks, and square feet per household.
    • Specific minimum lot-size measurements, on-site-sewage exceptions, platted-subdivision rules, and agricultural-parcel exceptions were not established from the opened HTML pages.
    • Applicable zoning approval must be obtained from the relevant township or municipality where required.
    “Each township and municipality has its own requirements such as minimum road frontages, setbacks, and square feet per household.”
  • SetbacksDistrict specific (with conditions)

    Township and municipal zoning setbacks in Union County.

    • Setbacks are controlled by the applicable township or municipal zoning authority.
    • Property corners should be located before digging so buildings are placed according to setbacks described on the zoning permit.
    “Each township and municipality has its own requirements such as minimum road frontages, setbacks, and square feet per household.”
    One more reviewed finding on this topic
    • District specific (with conditions) — Setbacks imposed by applicable township or municipal zoning authorities.
      “Each township and municipality has its own requirements such as minimum road frontages, setbacks, and square feet per household.”
  • Who permits septicCounty (with conditions)

    Household sewage treatment systems and semi-public systems in Union County.

    • The Union County Health Department administers the program under Ohio Revised Code Chapter 3718 and Ohio Administrative Code 3701-29.
    “The Union County Health Department permits and inspects household sewage treatment systems and semi-public systems as required by Ohio law”
    One more reviewed finding on this topic
    • County (with conditions) — Household and semi-public sewage treatment systems in Union County.
      “The Union County Health Department permits and inspects household sewage treatment systems and semi-public systems as required by Ohio law (Ohio Revised Code Chapter 3718 and in compliance with the rules set forth in Ohio Administrative Code 3701-29.”
  • Septic permitRequired

    New household sewage treatment systems and alterations in areas without public sewage service.

    • A sewage system installation permit and operating permit are required before installation.
    • A site and design application, installation permit, house plan, and soil report from a registered soil scientist must be submitted.
    • Alterations also require a permit and must be performed by a registered sewage contractor.
    • Public sanitary sewer connections are an exception to the household sewage treatment system renewal notice.
    “A sewage system installation permit and operating permit must be obtained from the Union County Health Department prior to installation.”
    One more reviewed finding on this topic
    • Required — New or altered household sewage treatment systems where public sewage service is unavailable or a private system is otherwise required.
      “A sewage system installation permit and operating permit must be obtained from the Union County Health Department prior to installation.”
  • Septic inspectionRequired

    Household sewage treatment systems in Union County.

    • The installer must schedule an inspection before backfilling a new system.
    • The Health Department performs a follow-up inspection 12 months after completion of a new installation.
    • Operation and maintenance inspections depend on system type; aerator and drip systems currently require inspections, and other systems follow the county inspection cycle.

    new-installation follow-up: 12 months · standard permit cycle: 5 years (Union County operation permits are renewed every five years)

    “The installer must call to schedule an inspection prior to backfilling the system. The Union County Health Department performs a follow-up inspection on all new system installations 12 months after the system is completed to evaluate system performance and provide homeowner education.”
    One more reviewed finding on this topic
    • Required — New and operating household sewage treatment systems in Union County.
      “The installer must call to schedule an inspection prior to backfilling the system. The Union County Health Department performs a follow-up inspection on all new system installations 12 months after the system is completed to evaluate system performance and provide homeowner education.”
  • Off-grid sanitationAllowed (with conditions)

    On-site household sewage treatment systems where public sewage service is unavailable.

    • A household sewage treatment system must be permitted and operated under Union County Health Department and Ohio sewage rules.
    • Site-specific soil, water-table, bedrock, slope, floodplain, and system-design factors may limit development.
    “If the property is not within the service area of a public sewage treatment plant or a development’s package plant, you will need to install a household sewage treatment system and identify a location for a backup system.”
  • Well permitRequired

    Private wells and underground water availability for residential development

    • A site inspection must be completed before the well permit is issued.
    • Requirements may depend on the property and applicable local or state rules.
    “Well and sewage disposal system permits are required from the Union County Health Department. A site inspection must be completed before the septic and well permit will be issued.”
    2 more reviewed findings on this topic
    • Required — Well permits for new development in Union County.
      “Well and sewage disposal system permits are required from the Union County Health Department. A site inspection must be completed before the septic and well permit will be issued.”
    • Required — New, altered, repaired, or abandoned private wells and other private water systems in Union County.
      “An Application for a Private Water System Permit must be filed with the Union County Health Department prior to digging a new well or installing another type of private water system, altering or repairing an existing system, or sealing/decommissioning a system no longer in use.”
  • Agricultural exemptionConditional

    Agricultural buildings determined by the township zoning inspector to have agricultural use

    • The township zoning inspector must determine the use is agricultural rather than residential accessory or commercial storage.
    • The exemption is from building-code regulations under ORC 3781.061.
    • Changing to residential or commercial use requires a change-of-occupancy permit and all code requirements for the new use.
    “If the township zoning inspector determines that the building’s use is agricultural rather than a residential accessory building or commercial storage building, then the building is exempt from building code regulations per ORC 3781.061.”
    2 more reviewed findings on this topic
    • Conditional — Agricultural buildings in Union County areas subject to township zoning determination.
      “If the township zoning inspector determines that the building’s use is agricultural rather than a residential accessory building or commercial storage building, then the building is exempt from building code regulations per ORC 3781.061.”
    • Conditional — Agricultural buildings determined by the applicable township zoning inspector to be agricultural rather than residential accessory or commercial storage buildings.
      “If the township zoning inspector determines that the building’s use is agricultural rather than a residential accessory building or commercial storage building, then the building is exempt from building code regulations per ORC 3781.061.”
  • Subdividing landRegulated (with conditions)

    Subdivision or sale of part of a property in Union County

    • The county guide directs applicants to the Union County Subdivision Regulations and the county Property & Survey office.
    • Additional local zoning, health, access, and floodplain requirements may apply.
    “If you wish to subdivide or sell off any part of your property, you must do so in accordance with the Union County Subdivision Regulations.”
    One more reviewed finding on this topic
    • Limited — Subdivision of land in the unincorporated areas of Union County, Ohio.
      “All subdivisions of land within the unincorporated areas of the County are regulated in accordance with the Subdivision Regulations of Union County.”
  • Driveway accessRequired

    New driveways along county and township roads

    • Driveway installations must comply with Requirements for Work Within Road Right-of-Way.
    • Access Management Regulations and Common Access Drive Regulations also control driveway locations.
    • State-highway driveways require contact with ODOT rather than the county Engineer.
    “The Union County Engineer issues permits for all new driveways along county and township roads. Driveway installations are permitted in accordance with the Requirements for Work Within Road Right-of-Way.”
    2 more reviewed findings on this topic
    • Required — New driveways in Union County.
      “A driveway permit is required if you plan to install a driveway.”
    • Required — New driveway installation along county or township roads in Union County.
      “The Union County Engineer issues permits for all new driveways along county and township roads. Driveway installations are permitted in accordance with the Requirements for Work Within Road Right-of-Way. Driveway locations are additionally controlled by the Access Management Regulations and Common Access Drive (CAD) Regulations.”
  • Building in a floodplainRequired

    Home construction within flood hazard areas in unincorporated Union County.

    • A flood hazard area permit is required for a home built within a flood hazard area.
    • Certain building restrictions apply.
    • Inside incorporated municipalities, check with city or village officials rather than the county.
    “Flood hazard area permits are required if your home will be built within a flood hazard area.”
    One more reviewed finding on this topic
    • Required — New construction, filling, or storage of materials within unincorporated Union County flood hazard areas.
      “The Union County Engineer is the floodplain manager for the unincorporated areas of Union County and is responsible for the administration and enforcement of Union County's Flood Damage Reduction Regulations. The regulations were adopted by the Union County Commissioners as required by the Federal Government. Flood Insurance Rate Maps (FIRM) as published by the Federal Emergency Management Agency (FEMA) serve as the basis for the regulations. Flood Hazard Permits are issued for any new construction or filling or storage of materials within these flood hazard areas.”
  • Permit feesPublished (with conditions)

    Residential building permit applications handled by the Union County Building Department where that department is the permitting authority.

    • The County Building Department provides residential building-code enforcement under agreements with municipalities, except Unionville Center, Plain City incorporated areas, and the City of Dublin; Dublin is the regulatory authority within incorporated Dublin and West Jefferson Building Department is the permitting authority for work inside Plain City incorporated areas.
    • Application and plan review fees are due when the permit is applied for and are non-refundable.
    • Permit refunds are at the discretion of the Building Official and are permitted only when the permit has not been issued.
    • A minimum of 100 square feet is used for calculating residential building areas; areas greater than 100 square feet are rounded up to the nearest hundred.
    • All residential building department fees have an additional 1% State of Ohio surcharge.
    • The schedule states fees are effective January 1, 2024.

    application fee: 35 USD (non-refundable and payable with permit application) · plan review fee for new, addition, alteration, or accessory building: 105 USD (non-refundable and payable with permit application) · building permit fee for new, addition, alteration, or accessory building: 95 USD (plus $10.00 per 100 square feet) · building permit fee for repair, replacement, or miscellaneous work: per 65 USD (per occurrence) · residential State of Ohio surcharge: 1 percent (additional surcharge on residential fees) · fee schedule effective date: 2024-01-01

    “UNION COUNTY ENGINEER DIVISION OF BUILDING REGULATIONS RESIDENTIAL FEE SCHEDULE Fees Effective: January 1, 2024”
    3 more reviewed findings on this topic
    • Variable (with conditions) — Union County residential and commercial building permits.
      “Building permits are based on square footage (as are electrical and HVAC) so the costs fluctuate depending upon the size of the project.”
    • Published (with conditions) — Union County commercial building permits and related inspections
      “COMMERCIAL FEE SCHEDULE Fees Effective: January 1, 2024”
    • Published (with conditions) — Commercial building permit applications handled by the Union County Building Department where that department is the permitting authority.
      “UNION COUNTY ENGINEER DIVISION OF BUILDING REGULATIONS COMMERCIAL FEE SCHEDULE Fees Effective: January 1, 2024”
  • Permit processPublished (with conditions)

    Building permit applications handled by the Union County Building Department.

    • Applicants submit the online application and construction drawings/specifications.
    • Plan approval, applicable township or municipal zoning approval, applicable Health Department approval, and fees are required.
    • Construction-drawing permits are required by state law to be reviewed within 30 days; permits without drawings are typically issued within one week.
    • Residential application and plan-review fees are due at submission; remaining fees are due after review and before issuance.
    • Commercial plan-review fees are due at submission and remaining fees when issued.
    • Permits are invalid if work has not commenced within 12 months, or if work is delayed or suspended for more than six months; extension requests are due at least 10 days before expiration.

    state-law plan review period: <= 30 days (Permits requiring construction drawings) · typical no-drawing issuance: 1 week (Typical time stated by county)

    “To obtain a building permit for your project, you will need to complete the following steps:”
    One more reviewed finding on this topic
    • Published (with conditions) — Union County building permit applications
      “Complete the appropriate application form through the Online Services portal and submit to the Union County Building Department along with any required construction drawings and specifications.”

Ohio rules that apply here

  • Owner-builder exemptionConditional

    Electrical and heating, ventilating, and air-conditioning work performed as contracting within an Ohio county; the statute authorizes, but does not itself impose, county licensing rules.

    • A board of county commissioners may adopt licensing rules by resolution for electrical and HVAC contractors not required to hold a valid and unexpired Chapter 4740 license.
    • County rules may be enforced in unincorporated areas and in municipalities that contract with the county for enforcement.
    • A county rule may require examinations, technical-skill demonstrations, fees, and additional licensing requirements.
    • A county board may accept a valid and unexpired Chapter 4740 license for construction, replacement, maintenance, or repair of one-, two-, or three-family dwellings or incidental accessory structures.
    • The statute does not establish a statewide owner-builder electrical or HVAC contractor-license exemption; county and municipal rules must be checked for the specific location.
    “Each board of county commissioners may adopt, by resolution, rules establishing standards and providing for the licensing of electrical and heating, ventilating, and air conditioning contractors who are not required to hold a valid and unexpired license pursuant to Chapter 4740. of the Revised Code.”
    2 more reviewed findings on this topic
    • Conditional — An owner-builder constructing, erecting, altering, or equipping a building covered by Ohio Revised Code section 3781.06, including residential buildings, where a certified municipal, township, or county building department has jurisdiction.
      “No owner shall proceed with the construction, erection, alteration, or equipment of any building until the plans or drawings, specifications, and data have been approved as this section requires, or the industrialized unit inspected at the point of origin.”
    • Conditional — An owner performing contractor-regulated construction, improvement, or renovation on the owner's own primary residential building in Ohio.
      “(F) "Construction project" means a construction project involving a building or structure subject to Chapter 3781. of the Revised Code and the rules adopted under that chapter, but not an industrialized unit or a residential building as defined in section 3781.06 of the Revised Code.”
  • Building heightDistrict specific (with conditions)

    Township zoning regulation of height for agricultural buildings or structures on lots greater than one acre but not greater than five acres in qualifying platted subdivisions or qualifying areas of fifteen or more contiguous lots.

    • The local regulation must arise under a township zoning resolution or amendment.
    • The subdivision or area must meet the statutory qualification in section 519.21(B).
    • The statute does not provide a statewide numeric height limit.
    • Township zoning may not regulate agriculture, agricultural buildings or structures, or dairying and animal and poultry husbandry on lots greater than five acres under division (B).

    lot size lower threshold: > 1 acre · lot size upper threshold: <= 5 acres

    “Buildings or structures incident to the use of land for agricultural purposes [...] height;”
  • Manufactured homesLimited

    Occupancy of manufactured homes installed in Ohio and regulated under Chapter 4781 of the Revised Code and implementing rules.

    • A manufactured home generally may not be occupied until the inspector issues the inspection seal.
    • The inspection seal must be paid for when the permit is issued.
    • A temporary occupancy permit may provide the applicable exception under Rule 4781-7-01(C).
    • The home must meet Ohio manufactured-home installation standards; local ordinances and other regulations may also apply to site placement.
    “Except as provided in paragraph (C) of this rule, no manufactured home shall be occupied until the inspector has issued the inspection seal.”
  • Mandatory utility hookupSewer (with conditions)

    Disposal of sewage where an existing publicly owned or regional sanitary sewer is accessible and available.

    • The sewer connection may not conflict with an areawide waste-treatment plan, approved regional sewage-service and treatment plan, or connection ban.
    • The receiving disposal system must have or be expected to have capacity to collect and treat the sewage.
    • For an existing structure, any part of the structure generating waste must be within 300 feet of the nearest sanitary-sewer right-of-way boundary.
    • For a proposed structure outside a larger common plan, any lot property line must be within 300 feet.
    • For two or more proposed structures, the threshold is 200 feet multiplied by the number of proposed structures, up to 5,000 feet.
    • The director may grant an exemption when technical, financial, environmental, legal, or physical barriers prevent connection and the alternative will not adversely affect human health or the environment.
    • When a sewer later becomes accessible and available, a non-public or non-regional disposal system must generally be abandoned and connection made within three years unless the director authorizes another timeframe.

    existing structure sewer-distance threshold: <= 300 feet (Measured to the nearest boundary of the sanitary-sewer right-of-way.) · proposed structure sewer-distance threshold: <= 300 feet (Measured from any property line of the lot.) · multiple proposed structures threshold: 200 feet multiplied by the number of proposed structures (Maximum distance is 5,000 feet.) · connection deadline after accessibility becomes available: 3 years (Unless an alternative timeframe is authorized by the director.)

    “Connection into existing publicly owned or regional sanitary sewers is required for the disposal of sewage when said sewers are accessible and available.”
  • Campground & park staysLimited

    Occupancy of recreational vehicles at Ohio campgrounds governed by Ohio Administrative Code Chapter 3701-26.

    • The rule applies to campground sites verified as complying with plans approved by the director or, for a temporary campground, by the licensor.
    • A site must be at least 1,000 square feet except as provided in paragraph (I)(11).
    • No more than one recreational vehicle and two portable camping units, or three portable camping units, may be permitted on one site.
    • Additional separation, sanitation, site-boundary, and licensed-capacity requirements apply.
    • This claim does not establish permission for long-term RV occupancy on ordinary private residential land outside a regulated campground.

    minimum campground site area: >= 1000 square feet (except as provided in paragraph (I)(11)) · maximum units per site: one recreational vehicle and two portable camping units, or three portable camping units

    “No more than the following number of units shall be permitted on any one site: (a) One recreational vehicle and two portable camping units, or (b) Three portable camping units.”
    3 more reviewed findings on this topic
    • Limited — Occupancy and placement of recreational vehicles in Ohio-licensed campgrounds and temporary campgrounds.
      “Recreational vehicles or portable camping units shall be parked only on sites that have been verified as complying with plans approved by the director, or in the case of a temporary campground, by the licensor;”
    • Prohibited — Camping in Ohio state forests outside areas, sites, or campgrounds designated by the chief of the division of forestry or an authorized agent.
      “No person shall camp in a state forest except in areas, sites or campgrounds designated by the chief of the division of forestry or authorized agent.”
    • Limited — Roadside camping at designated Ohio state forests along public roads maintained by the division of forestry.
      “Roadside camping is permitted at designated state forests, along public roads maintained by the division of forestry, during certain legally established hunting seasons as authorized by the chief of the division of forestry.”
  • county zoning authorityGeneral

    County commissioners may adopt zoning resolutions regulating building, structures, land uses, and districts or zones in unincorporated territory statewide.

    • The authority is exercised by resolution and must be in accordance with a comprehensive plan.
    • The authority applies to unincorporated territory of the county.
    • The statute begins with the exception phrase “Except as otherwise provided in this section,” so the limitations in ORC Chapter 303 apply.
    • For nonresidential property only, the county may regulate height, bulk, number of stories, size, lot coverage, yards, courts, open spaces, and population density.
    • Agricultural uses and agricultural buildings are subject to the limitations in ORC 303.21; the statute also contains limitations for public utilities, railroads, telecommunications towers, alcoholic-beverage sales, oil and gas drilling, and permanently sited manufactured homes.
    • Activities regulated under ORC Chapters 1513 and 1514 may be regulated only in the interest of public health or safety, and Chapter 1514 activities must be provided for as permitted or conditional uses as specified by ORC 303.02.
    “the board of county commissioners may regulate by resolution, in accordance with a comprehensive plan”
  • county building authorityGeneral

    County commissioners may adopt and enforce local residential building regulations in unincorporated areas and may operate certified county building departments that enforce state residential and nonresidential building codes, accept and approve plans, and conduct inspections.

    • Local residential building regulations may be enforced within the unincorporated area or within districts established in the unincorporated area.
    • A local residential building regulation may not differ from the state residential building code unless it addresses subject matter not addressed by that code or is adopted under ORC 3781.01.
    • An existing structures code must concern subject matter not addressed by, and may not conflict with, the state residential building code.
    • County building departments may enforce state codes only for the types of buildings and subject matters for which they are certified.
    • Certification permits enforcement authority, plan approval, and inspections; the certification application identifies whether it covers residential or nonresidential buildings and whether residential certification covers new construction only or also repair and alteration.
    • The board may adopt flood-hazard, Lake Erie coastal-erosion, and drainage regulations, subject to the statutory limits and exceptions in ORC 307.37.
    • Local regulations, codes, or amendments require public hearings at not fewer than two regular or special board sessions; they take effect on the thirty-first day after adoption.
    • Regulations adopted under ORC 307.37 generally do not affect buildings or structures existing, or under construction, before adoption, except as provided for an existing structures code.
    • The state residential building code is effective as a uniform requirement in areas with a building department certified to enforce it.
    “The board of county commissioners may adopt local residential building regulations governing residential buildings as defined in section 3781.06 of the Revised Code”
    One more reviewed finding on this topic
    • General — Ohio boards of county commissioners adopting and enforcing local residential building regulations in unincorporated county areas, including districts established within those areas, and administering state building codes when certified.
      “The board of county commissioners may adopt local residential building regulations governing residential buildings”

Set by your township or city, not the county

In Ohio, zoning is adopted by each township or city, so Union County has no county-wide answer on these. Find your township or city in the list of places on this page, or call its clerk or zoning administrator.

  • Zoning districts
  • Lot coverage
  • Camping on your land
  • Tiny homes
  • Accessory dwellings
  • Short-term rentals

Each answer was extracted from an official source and independently re-checked against that source by a second reviewer. That is an evidence check, not legal advice. Rules change; confirm with the authority before you buy or build.

Living off-grid in Union County, Ohio

Is Union County a good place to live off-grid or homestead?

Union County scores 41/100 on the Bolthole Index, a marginal county profile. Its strengths: a durable current and mid-century hazard profile and manageable long-term carry cost. Watch-outs: about 89,000 people within a 30-minute drive and a weaker property-autonomy legal backdrop.

Do you need a building permit in Union County, Ohio?

Union County generally requires a residential building permit, and it has no county-wide zoning. Onsite septic is permitted by Union County Health Department (under Ohio DoH, ORC 3718 / OAC 3701-29). Owner-builders may act as their own contractor to build their home. These answers are quoted from official sources and independently re-checked. Rules change and cities within the county differ — always confirm with the county before you buy or build.

How much does land cost in Union County, Ohio?

Land in Union County runs about $8,151 per acre, based on the latest county data.

What is the water situation in Union County?

Union County gets about 39.4" of rain a year, with severe drought in roughly 0.8% of years.

How remote is Union County?

A representative private-land location has about 89,000 people within a 30-minute drive and 6,238,746 within two hours. The road-network catchments count population across county lines and clusters of smaller cities; straight-line radius values remain available as a comparison.

How Union compares in Ohio

Compare side-by-side →See all 88 Ohio counties ranked →