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 several incorporated places use other authorities12. Zoning is handled by the applicable township or municipality and varies by district3. For land beyond public sewer service, the Union County Health Department permits and inspects septic systems4.

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 Township3
Septic permits
Installation and operating permits from the Union County Health Department5
Owner-builder exemption
Unconfirmed; no explicit owner-builder statement found on the county's own pages6
Agricultural building exemption
Conditional on the township zoning inspector determining that the use is agricultural7
Minimum home size and setbacks
Set by the applicable township or municipality, not by one countywide standard89
Private well
A county health permit and site inspection are required before issuance10

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

[email protected]

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

[email protected]

940 London Avenue, Suite 1100, Marysville, Ohio 43040

Contact details are copied from each office’s official page and were checked against it on September 29, 2026.

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 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 requirements7.

Who issues building permits in Union County, 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 Marysville11. Applicants submit the online application with drawings and specifications, then secure plan approval, local zoning approval, any required Health Department approval and payment of fees12. Applications with construction drawings must be reviewed within 30 days, while permits without drawings are typically issued within 1 week12. Residential application and plan-review fees are due when the application is submitted; the balance is due after review and before issuance12. Construction must wait until the permit is issued1. Contact the alternative building authority instead if the parcel is in Unionville Center, incorporated Plain City or Dublin2.

Does Union County have zoning?

Zoning in Union County is administered by the applicable township or municipality, and zoning permits are required in most municipalities and all townships except Jackson Township3. Minimum road frontage, setbacks and minimum square feet per household vary with the local district389. That means a parcel's mailing address alone 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 permit exception does not erase other applicable building, septic, well, driveway or floodplain requirements315101314. Union County's own building workflow treats local zoning approval as a separate prerequisite where required12.

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 system15. 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 Department5. 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 type16. 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 location17. Site-specific soil, water table, bedrock, slope and floodplain conditions can constrain the approved design15.

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 buying389. 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 pre-permit site inspection1510. A manufactured home generally cannot be occupied until the state inspector issues its inspection seal, apart from the temporary-occupancy exception18.

Building a home in Union County: the steps, in order

  1. Identify the township or municipality and confirm permitted use, minimum dwelling size, frontage and setbacks with its zoning official389.
  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 process5.
  4. Apply for the private-well permit and complete the required site inspection if the home will use a well10.
  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 highway13.
  6. If the site is in a flood hazard area, obtain the county flood-hazard permit for unincorporated land or check with the city or village inside a municipality14.
  7. Submit the building application and drawings, secure the required approvals, pay the fees, and wait for permit issuance before starting work121.

What to check before you buy land in Union County

Confirm four buildability issues before closing: septic capacity, water, legal access and floodplain status. 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 application175. A private well needs a permit and site inspection10. A new driveway needs approval from the Union County Engineer on a county or township road, or from the Ohio Department of Transportation on a state highway13. A home in a flood hazard area needs a flood-hazard permit in unincorporated Union County, while incorporated sites go through city or village officials14. Also verify the governing zoning district because setbacks, road frontage and minimum dwelling size vary locally3. Typical farmland value is about $8,151 per acre, and the median annual property-tax bill is about $3,8471920.

Watch-outs

  • Zoning requirements vary by township and municipality; Jackson Township is the township exception to the local zoning-permit requirement3.
  • 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 evaluation17.
  • 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 deadlines11.

Sources

  1. Ready, Set, Build!, quoted and re-checked
  2. Building Dept FAQ, quoted and re-checked
  3. Ready, Set, Build!, quoted and re-checked
  4. Septic Systems, quoted and re-checked
  5. Septic Systems, quoted and re-checked
  6. (2026 county census)
  7. Building Dept FAQ, quoted and re-checked
  8. Ready, Set, Build!, quoted and re-checked
  9. Ready, Set, Build!, quoted and re-checked
  10. Ready, Set, Build!, quoted and re-checked
  11. Union County Building Department (Engineer's Office, Building Regulation) (unioncountyohio.gov)
  12. Building Dept FAQ, quoted and re-checked
  13. Ready, Set, Build!, quoted and re-checked
  14. Ready, Set, Build!, quoted and re-checked
  15. Septic Systems, quoted and re-checked
  16. Septic Systems, quoted and re-checked
  17. Share of soils without severe limits for a conventional septic drain field (USDA SSURGO): Bolthole Index county data
  18. Chapter 4781-7 | Manufactured home inspections (Ohio statewide rule), quoted and re-checked
  19. Farmland value per acre (USDA census): Bolthole Index county data
  20. Median property tax bill: Bolthole Index county data

Written September 29, 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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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%Septic soil without severe limits
379 acWorkable land screen
12.9%Wooded land
26.6 tonsBiomass / forest ac
51.6°FAvg temp

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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 areas served by the Union County Building Department.

    • Only work not requiring a permit or emergency repairs may proceed without a permit.
    • Residential sheds of 200 square feet or less and commercial sheds of 120 square feet or less are exempt.
    • Patios do not require a building permit, but a zoning permit may be required.
    • Agricultural buildings may be exempt under ORC 3781.061 when the township zoning inspector determines the use is agricultural.
    • Construction may begin only after the permit is issued.
    “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)

    Construction reviewed by the Union County Building Department in its service area.

    • Building-code enforcement is not provided by Union County in Unionville Center, incorporated Plain City, or the City of Dublin; Dublin is regulated by its own building department and West Jefferson Building Department is the permitting authority for incorporated Plain City.
    “The Union County Building Department will review construction documents ensuring the proposed work conforms to the adopted building codes.”
  • Local zoningVaries (with conditions)

    Local zoning across Union County, aggregated across townships and municipalities.

    • Zoning is administered by the applicable township or municipality.
    • Zoning permits are required in most municipalities and all townships except Jackson Township.
    • Each township and municipality has its own requirements, including minimum road frontages, setbacks, and square feet per household.
    “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)

    Minimum dwelling-size or square-foot requirements imposed by applicable township or municipal zoning authorities.

    • Requirements vary by township and municipality; the county guide does not provide a countywide numeric minimum.
    “Each township and municipality has its own requirements such as minimum road frontages, setbacks, and square feet per household.”
  • SetbacksDistrict specific (with conditions)

    Setbacks imposed by applicable township or municipal zoning authorities.

    • Setback requirements vary by township and municipality and must be confirmed with the applicable zoning official.
    “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 and semi-public sewage treatment systems in Union County.

    • Ohio law and Ohio Administrative Code establish the governing framework; the Union County Health Department administers permitting and inspections locally.
    “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.”
  • 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.”
  • 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

    Well permits for new development in Union County.

    • A site inspection must be completed before the well permit is issued.
    • The reviewed source does not specify the full well-permit application requirements.
    “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.”
  • Agricultural exemptionConditional

    Agricultural buildings in Union County areas subject to township zoning determination.

    • The township zoning inspector must determine that the use is agricultural rather than residential accessory or commercial storage.
    • The exemption is from building-code regulations under ORC 3781.061.
    • Changing the building 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.”
  • Driveway accessRequired

    New driveways in Union County.

    • For driveways along county or township roads, apply to the Union County Engineer.
    • For driveways along a state highway, contact the Ohio Department of Transportation.
    • The official guide does not specify the permit fee or design standards.
    “A driveway permit is required if you plan to install a driveway.”
  • 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.”
  • 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:”
  • County-wide zoningPresent

    Zoning is administered at the township and municipal level; county building materials note a zoning permit may be required and that projects need applicable township/municipality approval.

    Union County - Building Dept FAQ ↗Scouted from the county site, not yet independently re-checked

Ohio rules that apply here

  • InspectionsRequired

    Building work subject to Ohio building-code enforcement after certificate of plan approval, and inspections initiated after complaints, accidents, or natural disasters.

    • Inspections are directed after a certificate of plan approval has been issued, or after a complaint, accident, or natural disaster.
    • The building official identifies special conditions affecting inspection timing and schedules inspection times mutually agreed upon by the building official and owner.
    • Special inspections required under section 1704 of rule 4101:1-1-01 are excepted from the stated scheduling rule.
    • Certified inspectors inspect work within the limits of their certification and the approved construction documents.
    “Once a certificate of plan approval has been issued in accordance with rule 4101:1-1-01 or 4101:8-1-01 of the Administrative Code, or upon receipt of a complaint or occurrence of an accident or natural disaster, the building official directs necessary inspections and investigations to determine whether the work which has been performed and the installations which have been made are in conformity with the approved construction documents.”
  • 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.”
  • Subdividing landRegulated (with conditions)

    Subdivision and platting of land in Ohio, including divisions of parcels and plats outside municipal corporations.

    • A subdivision includes division of a parcel into two or more parcels, sites, or lots when any one is less than five acres for immediate or future transfer of ownership.
    • A division or partition into parcels of more than five acres is exempt when it does not involve new streets or easements of access.
    • A sale or exchange between adjoining lot owners is exempt when it does not create additional building sites.
    • A planning authority may adopt a rule under section 711.133 exempting parcels of four acres or more within the size range delineated in that rule.
    • Improvement of land involving division or allocation for opening, widening, or extension of public or private streets, or for common open spaces or utility easements, is also included in the statutory subdivision definition.
    • No plat certifying lands outside a municipal corporation may be recorded without approval by the board of county commissioners, except where approval is required from a planning commission under sections 711.09 or 711.10.
    • The cited section 711.001 states an effective date of July 1, 2010; the cited section 711.041 states an effective date of October 6, 1955.

    subdivision parcel threshold: < 5 acres (The statutory definition applies when any resulting parcel, site, or lot is less than five acres.) · exempt parcel size: > 5 acres (Division or partition into parcels of more than five acres is exempt if no new streets or easements of access are involved.) · possible planning-authority exemption threshold: >= 4 acres (Only if the planning authority adopts a rule under section 711.133 and only within the size range delineated in that rule.)

    “No plat certifying lands outside a municipal corporation may be recorded without the approval thereon of the board of county commissioners”
  • Permit feesPublished (with conditions)

    Construction documents and inspections required to be submitted to the Ohio Division of Industrial Compliance.

    • The certificate of occupancy or certificate of completion will not be issued until applicable fees are paid.
    • The schedule includes a $275 processing fee for structural, mechanical, electrical, fire alarm, and sprinkler scopes; plan-examination fees vary by scope and area or device count.
    • One initial plan review and up to two resubmission plan reviews are included; additional resubmissions cost $100 each.
    • Additional inspections cost $150 per inspection; reinspections cost $150.
    • Certificates of occupancy or completion cost $65, except existing-building certificates issued under rule 111.4 have no fee.
    • The rule was effective January 1, 2019 and was last updated July 14, 2026.

    structural processing fee: 275 USD · certificate of occupancy or completion fee: 65 USD (No fee for existing-building certificates issued under rule 111.4)

    “The fees for examination and processing of construction documents when required to be submitted to the division of industrial compliance, except medical gas piping systems and temporary structures, shall be in accordance with Table B1.”
    One more reviewed finding on this topic
    • Variable (with conditions) — Construction-document submissions and inspections handled by certified municipal, township, or county building departments in Ohio.
      “Fees for construction documents submitted to and inspections made by certified building departments shall be in accordance with the locally adopted fee schedule.”
  • Campground & park staysLimited

    Occupancy and placement of recreational vehicles in Ohio-licensed campgrounds and temporary campgrounds.

    • Recreational vehicles may be parked only on sites verified as complying with plans approved by the director, or, for a temporary campground, by the licensor.
    • A campground site may contain no more than one recreational vehicle and two portable camping units, or three portable camping units.
    • Sites generally must be at least 1,000 square feet, subject to the temporary-campground density exception determined by the licensor where open fires are prohibited.
    • Separation, sanitation, sewage, gray-water, and licensed-capacity requirements also apply.

    minimum campground site area: >= 1000 square feet (Except as provided in paragraph (I)(11) for temporary campgrounds.) · recreational vehicles per site: 1 vehicle (A site may also contain two portable camping units; alternatively, a site may contain three portable camping units.)

    “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;”
    2 more reviewed findings on this topic
    • 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”

Still unanswered

We looked and could not find an official answer yet. Silence is not permission — ask the county directly.

  • Owner-builder exemption — Owner-builder exemptions from Union County building requirements.
  • Certificate of occupancy — Certificates of occupancy for Union County buildings.
  • Minimum lot size — Minimum lot size in Union County.
  • Lot coverage — Lot-coverage limits in Union County.
  • Building height — Building-height limits in Union County.
5 more unanswered
  • Living in an RV
  • 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 enforces county zoning. Onsite septic is permitted by Union County Health Department (under Ohio DoH, ORC 3718 / OAC 3701-29). 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.

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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How Union compares in Ohio

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