Bolthole Index

Washington County, Iowa

Building permits, zoning and septic rules in Washington County, Iowa

64Index Score / 100
#22 of 99 in Iowa

Unincorporated Washington County, Iowa does not require a building permit for a building project: the county has not adopted any building codes1. Washington County also has no zoning ordinance for unincorporated land; the county's former zoning ordinance was rescinded in 20132. Septic and well permits still go through the county, not the state, by way of Washington County Environmental Health34. Floodplain development, driveway entrances and subdivisions all have their own rules, so read on before assuming nothing applies to your land56.

At a glance

Building permit
Not required; Washington County has not adopted any building codes1
Zoning
None; the county's zoning ordinance was rescinded in 20132
Septic / well permit
Required, issued by Washington County Environmental Health3
Owner-builder exemption
Yes; with no county building permit there is no permit to be exempt from7
Floodplain development permit
Required before any development in the mapped floodplain, including farm buildings8
Subdivision review
Minor subdivisions are 2 to 5 lots; major subdivisions are 6 or more lots9
County-road driveway permit
Required before building a new entrance onto a county road10
Manufactured homes
State law bars a county from disallowing a manufactured home solely because it's manufactured11

Who to call

Planning & zoning

Washington County Planning & Development

Publishes the county's rural building and development permit guidance, administers the subdivision ordinance, and is the office to call about extraterritorial (within-two-miles-of-a-city) questions

319-653-7710

Washington County Courthouse, 222 W Main St, Washington, IA 52353

Septic permits

Washington County Environmental Health

Issues well and septic permits and inspections for unincorporated Washington County

319-653-7782

[email protected]

2175 Lexington Blvd. Bldg 2, Washington, IA 52353

Floodplain permits

Washington County Environmental Health (Floodplain Administrator)

Reviews and issues Floodplain Development Permits for development in the mapped 100-year floodplain

319-653-7782

[email protected]

2175 Lexington Blvd. Bldg 2, Washington, IA 52353

Roads & driveways

Washington County Engineering & Secondary Roads

Reviews and approves new or modified driveway entrances onto Washington County roads and maintains the county's secondary road network

319-653-7731

703 E. 7th Street, Washington, IA 52353

Contact details are copied from each office’s official page and were checked against it on September 24, 2026.

Do you need a building permit in Washington County, Iowa?

Washington County has not adopted any building codes, so no county building permit is required for a building project in the unincorporated area1. That means there is no county building-code review, inspection, or county-issued building permit to apply for on a typical rural home12. Other permits can still apply to the same project: a floodplain development permit is required before any work in the mapped 100-year floodplain, and a driveway entrance permit is required before building a new entrance onto a county road810. If your land sits within two miles of an incorporated city, contact that city first, since it may enforce its own building or zoning codes on rural property that close13.

Who is the Washington County building department, and how do you reach them?

Washington County has no separate building department, since it has not adopted a building code14. The Washington County Planning & Development Department, based at the county courthouse, publishes the county's rural building and permit guidance and administers subdivision review15. Floodplain development permits and well or septic questions go to Washington County Environmental Health instead, and new county-road entrances go through Engineering & Secondary Roads56. State-regulated electrical work still needs its own inspection: all new electrical work in the county must be done by a state-licensed electrical contractor and inspected under state law, separate from any county office14.

Does Washington County have zoning?

Washington County has no zoning ordinance for unincorporated land: its former zoning ordinance took effect July 1, 2010 and was rescinded on September 27, 2013216. Iowa law lets a county's board of supervisors adopt zoning for land outside city limits, but even where a county does zone, the ordinance generally cannot reach agricultural land, farmhouses, farm barns or other structures used for farming, apart from floodplain provisions17. Because Washington County currently has no zoning ordinance, no county zoning permit or district review applies to unincorporated land today2. That does not remove every rule: the county's subdivision ordinance still governs how land can be divided, and its floodplain, driveway-entrance and septic rules apply regardless of zoning status9. Land within two miles of an incorporated city may fall under that city's own building or zoning rules even though the county has none, so check with the city first13.

How do septic and well permits work in Washington County?

Washington County, not the state, issues septic and well permits in the unincorporated area: Washington County Environmental Health administers private onsite wastewater systems under Iowa Administrative Code Chapter 69 and Chapter 66 of the county's own ordinances318. Contact the department before finalizing plans for a new well or a new or additional septic system, since both go through the same office4. Iowa law splits septic oversight between the state and counties: county boards of health must enforce standards at least as strict as the state's, while the Iowa Department of Natural Resources keeps its own authority over direct discharges19. None of Washington County's soils are rated free of severe limits for a conventional septic drain field, so budget for an engineered or alternative system rather than assuming a standard drain field will work20. Before any qualifying property sale, Iowa law requires a certified inspector to open and pump the septic tank and file a report, and that inspection is valid for 2 years for ownership-transfer purposes; a county recorder generally cannot record the deed without it21.

Can you live in an RV, mobile home or tiny home on your land in Washington County?

Washington County's official guidance confirms that no county zoning permit is required in the unincorporated area, but its published pages do not state whether long-term RV occupancy, tiny-home occupancy or manufactured-home placement is allowed, limited or prohibited2. That gap matters because the county still enforces other rules that can reach these structures: a floodplain development permit is required before placing a mobile home in the mapped floodplain, and any new well or septic system for a dwelling has to go through Washington County Environmental Health first84. Iowa law does not let a county zoning ordinance disallow a manufactured home solely because it is manufactured, and requires it to meet the same foundation, setback and minimum-size standards as a site-built home on the same lot, though Washington County currently has no zoning ordinance to apply that standard against11. Because RV and tiny-home occupancy specifically is not addressed on any official Washington County page found for this guide, call the Planning & Development Department before you buy or place one15.

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

  1. Confirm the parcel is in unincorporated Washington County, where no county building permit or zoning permit is required12.
  2. If the parcel is within two miles of an incorporated city, call that city to see whether it enforces its own building or zoning rules there13.
  3. Apply for a well or septic permit with Washington County Environmental Health before finalizing your site plan418.
  4. If any part of the project is in the mapped 100-year floodplain, get a Floodplain Development Permit before starting work; the application costs $5058.
  5. Before building a new entrance onto a county road, get a driveway entrance permit: the county requires a minimum 16-foot entrance top, a minimum 30-foot culvert pipe, and 48 hours' written notice to the County Engineer before construction610.
  6. If the entrance is instead onto a state highway, contact the Iowa Department of Transportation for its own access permit22.
  7. If the lot was created by dividing a larger tract, check whether it falls under the county's minor-subdivision rules (2 to 5 lots) or major-subdivision rules (6 or more lots) before you finalize a purchase9.
  8. Before selling or transferring the finished home later, plan for Iowa's required certified septic inspection, needed before the deed can be recorded21.

What to check before you buy land in Washington County

Soils: 0% of Washington County's soils are rated free of severe limits for a conventional septic drain field, so plan on an engineered or alternative system and get a site evaluation from Environmental Health before you buy204. Terrain: 93.9% of the county's land sits at 15% slope or less and only 10.8% is wooded, so this is flat, largely cleared farm country rather than timbered acreage2324. Federal land: just 1.3% of Washington County is federally owned, so nearly all rural land here is private25. Flood risk: check whether the parcel falls in the mapped 100-year floodplain, since a Floodplain Development Permit is required for any development there, farm buildings included, with no farmer exemption268. Access: a new driveway onto a county road needs an entrance permit from the County Engineer, and one onto a state highway needs an Iowa DOT permit instead622. Subdividing: dividing land for agricultural use only can skip the subdivision ordinance's application, review and fees if it meets the plat-of-survey requirements27. Taxes: Washington County's effective property tax rate runs about 1.3%, with a median annual property tax bill around $2,6882829. Market: the typical home value is about $238,708 and farmland runs roughly $9,552 an acre, among the more productive cropland ground in the state3031.

Watch-outs

  • Washington County's own guidance does not say whether RV, tiny-home or manufactured-home occupancy on an individual lot is allowed, limited or prohibited; confirm with the Planning & Development Department before you buy or move one onto rural land15.
  • A floodplain permit applies even to farm buildings: sheds, bins, tanks and farmhouses in the mapped floodplain all need a Floodplain Development Permit, with no farmer exemption26.
  • If your land is within two miles of an incorporated city, that city, not the county, may control building or zoning there, even though Washington County itself has no zoning ordinance13.

Sources

  1. Rural Building & Development Permits (2026 county census)
  2. Zoning Ordinance (Rescinded on September 27, 2013) (2026 county census)
  3. Private Onsite Septic Systems (2026 county census)
  4. Washington County Environmental Health (washingtoncounty.iowa.gov)
  5. Washington County Environmental Health (Floodplain Administrator) (washingtoncounty.iowa.gov)
  6. Washington County Engineering & Secondary Roads (washingtoncounty.iowa.gov)
  7. Rural Building & Development Permits (2026 county census)
  8. Instructions – Floodplain Development Permit, quoted and re-checked
  9. Subdivision & Platting, quoted and re-checked
  10. Chapter 37 - Rights-of-Way, quoted and re-checked
  11. Iowa Code §335.30, Manufactured and modular homes (Iowa statewide rule), quoted and re-checked
  12. Rural Building & Development Permits, quoted and re-checked
  13. Rural Building & Development Permits, quoted and re-checked
  14. Rural Building & Development Permits, quoted and re-checked
  15. Washington County Planning & Development (washingtoncounty.iowa.gov)
  16. Zoning Ordinance (Rescinded on September 27, 2013), quoted and re-checked
  17. Iowa Code 2026, Chapter 335 — County Zoning (Iowa statewide rule), quoted and re-checked
  18. Private Onsite Septic Systems, quoted and re-checked
  19. Iowa Code §455B.172, Jurisdiction of department and local boards (Iowa statewide rule), quoted and re-checked
  20. Share of soils without severe limits for a conventional septic drain field (USDA SSURGO): Bolthole Index county data
  21. Iowa Code §455B.172, Jurisdiction of department and local boards (Iowa statewide rule), quoted and re-checked
  22. Access Management (Iowa statewide rule), quoted and re-checked
  23. Share of land at 15% slope or less: Bolthole Index county data
  24. Wooded share of land: Bolthole Index county data
  25. Federal land share: Bolthole Index county data
  26. Floodplain FAQ, quoted and re-checked
  27. Washington County Subdivision & Platting Ordinance, amended September 19, 2024, quoted and re-checked
  28. Effective property tax rate: Bolthole Index county data
  29. Median property tax bill: Bolthole Index county data
  30. Typical home value (Zillow): Bolthole Index county data
  31. Farmland value per acre (USDA census): Bolthole Index county data

Written September 24, 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

Washington County in Iowa

64
County map
Washington County highlighted among the Iowa counties · colored by Index score

How Washington County scores

Seclusion46100% ev.
Self-Sufficiency46100% ev.
Admin Boringness91100% ev.
Durability56100% ev.
Property Autonomy51100% ev.
Carry Cost58100% ev.

Evidence strength: 100%. This reports direct-source completeness and fallback use; it is separate from the score and is not a confidence interval. How it works →

$239kTypical home
1.3%Property tax
$9,552Land / acre
38"Annual rain
11.8% of yrsSevere drought
7.4 / yr (+6.5)Mid-century 100°F days
15.5 daysMid-century dry spell
1.95" (+11%)Mid-century 1-day rain
1.8×Wildfire change factor
100%Forward climate coverage
$1,602Home insurance / yr
2.5% / yrInsurance growth
1.24%Nonrenewal rate
county median (2+ published ZIPs)Insurance basis
31,320People within 30 min
1,560,861People within 2 hr
23,223Radius comparison (15 mi)
39.7People / sq mi
1.3%Federal land
93.9%Land at 15% slope or less
0%Septic soil without severe limits
0 acWorkable land screen
10.8%Wooded land
54.5 tonsBiomass / forest ac
50°FAvg temp

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Answers from the rulebook for Washington County

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

Washington County rules

  • Building permitNot required

    Building projects in the unincorporated areas of Washington County, Iowa.

    • Washington County has not adopted any building codes.
    • Other permits may be required for certain projects.
    • A floodplain development permit is required before starting a project located in the 100-Year Floodplain.
    • State electrical permits and inspections may apply.
    • For projects within two miles of an incorporated city, the city should be contacted to determine whether it enforces building or zoning codes and requires permits in the rural location.
    • The source does not establish the rule for incorporated municipalities.
    “BUILDING PERMITS – Washington County has not adopted any building codes and therefore a county building permit is not required for building projects located in the unincorporated areas. However, other permits may be required for certain projects.”
  • Owner-builder exemption · follows from the permit answerNot needed

    Unincorporated Washington County: no county building permit is required, so there is no permit to be exempt from and you may build your own home. State licensing for electrical, plumbing and HVAC work may still apply.

    • Washington County has not adopted any building codes.
    • Other permits may be required for certain projects.
    “BUILDING PERMITS – Washington County has not adopted any building codes and therefore a county building permit is not required for building projects located in the unincorporated areas. However, other permits may be required for certain projects.”
  • Building code adoptedNot adopted

    County building-code adoption and county building permits for building projects in Washington County's unincorporated areas.

    • Washington County states that other permits may be required for certain projects.
    • The same county source states that the State enforces Iowa Code chapter 103 and requires inspection of all new electrical work within the county, with electrical contractors required to be state licensed.
    • A floodplain development permit is required before starting projects located in the 100-year floodplain, subject to the source's stated scope and exceptions.
    • If a project is within two miles of an incorporated city, the city should be contacted to determine whether it enforces building or zoning codes and requires permits.
    “Washington County has not adopted any building codes”
  • County-wide zoningAbsent

    County zoning permits and the former county zoning ordinance for uses and building projects in Washington County's unincorporated areas.

    • The former Washington County Zoning Ordinance became effective July 1, 2010 and was rescinded September 27, 2013.
    • Other Rural Building & Development Permits may still be required depending on the project.
    • This claim does not determine zoning administered by incorporated municipalities.
    “The Washington County Zoning Ordinance, which became effective July 1, 2010, was rescinded on September 27, 2013.”
  • Local zoningVaries (with conditions)

    Local zoning or building-code controls affecting rural property within two miles of an incorporated city in Washington County.

    • The county instructs applicants within two miles of an incorporated city to contact the city to determine whether the city enforces building or zoning codes in the rural location.
    • The county does not state in this source which incorporated cities enforce such codes or identify the applicable municipal ordinances.
    • The county's own zoning ordinance was rescinded, so this aggregate conclusion concerns possible municipal or extraterritorial controls rather than county-administered zoning.

    distance from incorporated city: <= 2 miles (The source says 'within two miles'.)

    “contact the City to determine if they enforce any building or zoning codes”
  • Who permits septicCounty

    Private onsite wastewater systems in Washington County, including unincorporated county areas.

    • The county page identifies Washington County requirements under Iowa Administrative Code Chapter 69 and Chapter 66 of the Washington County Code of Ordinances.
    • Washington County Environmental Health is responsible for septic system inspections.
    “Chapter 567-69 of the Iowa Administrative Code, entitled “On-site Wastewater Treatment and Disposal Systems,” is adopted and incorporated by reference as if fully set forth herein.”
  • Agricultural exemptionAvailable (with conditions)

    Plat-of-survey divisions of land in unincorporated Washington County that have been and will remain agricultural use.

    • The division must have been and will remain Agricultural Use.
    • The plat is exempt from the application procedure, departmental review, and fees otherwise required by the subdivision ordinance.
    • The plat must meet §§45.23, 45.24, and 45.25.1 and be submitted to the Subdivision Coordinator for review and signature.
    • The plat must state that the parcel is valid for agricultural use only.
    “A Plat of Survey for the division of land which has been and will remain Agricultural Use shall be exempt from the application procedure, departmental review and fees otherwise required by this ordinance.”
    One more reviewed finding on this topic
    • Not available (with conditions) — Agricultural development in Washington County floodplains, including farmhouses, farm buildings, bins, sheds, tanks, and other outbuildings.
      “No, all development in the floodplain, including farmhouses, farm buildings, bins, sheds, tanks and other outbuildings requires a Floodplain Development Permit.”
  • Subdividing landRegulated (with conditions)

    All plats, corrections, modifications, vacations, and land divisions constituting subdivisions in unincorporated Washington County, subject to the ordinance's exemptions and special procedures.

    • The ordinance applies to all unincorporated territory or land in Washington County and to plats, corrections, or modifications submitted after adoption.
    • Major subdivisions include six or more lots without improvements fronting an existing street, or two or more lots requiring major improvements including streets.
    • Minor subdivisions generally involve two to five lots fronting an existing street without new major improvements.
    • Exemptions or partial exemptions include cemetery burial lots, acquisition plats, auditor's plats, vacations and corrections, divisions into one-quarter, one-half, or forty acres or more without a new street, easement, or dedication, agricultural-use plat-of-survey divisions, state right-of-way divisions, retracement plats, and the first-split rule.
    • Agricultural-use plat-of-survey divisions remain subject to specified plat, monument, and survey requirements and must state that the parcel is valid for agricultural use only.
    • Within municipal extraterritorial areas, both the municipality and county may review unless a 28E or similar agreement governs.

    major subdivision threshold: 6 or more lots without improvements, or 2 or more lots requiring major improvements including streets · minor subdivision threshold: 2 to 5 lots total, fronting an existing street, without new major improvements

    “The Subdivision Ordinance of Washington County, Iowa, shall apply to all of the unincorporated territory or land in Washington County, Iowa. This ordinance applies to all plats, corrections or modifications of plats and vacations submitted after the date of adoption of this Ordinance.”
  • Driveway accessRequired

    New entrance locations and changes or modifications to existing entrances onto Washington County roads.

    • The County Engineer determines adequate sight distance, slope, culvert requirements, entrance dimensions, and other criteria.
    • A minimum 16-foot entrance top and minimum 30-foot culvert pipe are required where applicable.
    • Entrances on gravel or dirt roads must have 3:1 side slopes; entrances on paved roads must have 8:1 side slopes for culverts and 10:1 side slopes for dry fills.
    • Written notice must be given to the County Engineer at least 48 hours before construction.
    • Final approval requires inspection and approval by the County Engineer or authorized agent.
    • The property owner or tenant is responsible for initial entrance construction and materials; Washington County does not provide dirt, pipe, or other materials.

    minimum entrance top: >= 16 feet · minimum culvert pipe length: >= 30 feet · minimum culvert pipe size: >= 15 inches · advance written notice: >= 48 hours (before commencement of construction)

    “Permit Required - Anyone creating a new entrance location or any change or modification of an existing entrance onto County roads shall first be required to obtain a permit as required in the preceding section. (Driveway Permit )”
  • Permit processPublished (with conditions)

    Floodplain development in the mapped 100-year floodplain Zone A areas of Washington County.

    • The application must be complete and include owner/builder information, property location, work description and future use, site plan, 100-year flood elevation from Iowa DNR, lowest-floor or floodproofing elevation, and owner signature in ink.
    • For nonconforming uses or structures, contractor’s bid, appraisal, assessor record, and plans or drawings are also required.
    • If an existing structure is substantially damaged at 50% or greater damage from any event, it must be elevated at least one foot above the 100-year base flood elevation or floodproofed and meet Floodplain Management Ordinance 13-1.
    • The completed application is submitted to the Floodplain Administrator; staff normally review it within one week, and work may commence upon receipt of the permit.

    substantial damage threshold: >= 50 percent (damage from any event) · elevation above 100-year base flood elevation: >= 1 foot (or floodproofing) · normal staff review time: within one week

    “Application Review: After receiving a completed application, the forms are normally reviewed by staff within one week. If all applicable provisions of the Washington County Floodplain Development Ordinance are satisfied a Flood Plain Development Permit will be mailed. Your project can commence upon receipt of this permit.”

Iowa rules that apply here

  • InspectionsLimited

    Buildings and structures subject to Iowa Code section 103A.10A, including newly constructed state-owned buildings, state-board-of-regents buildings, and certain state-funded buildings.

    • Newly constructed state-owned buildings and structures subject to the state building code are subject to plan review and inspection, excluding renovations and repairs except as provided by statute.
    • Newly constructed buildings owned by the state board of regents are subject to plan review and inspection, excluding renovations and repairs except as provided by statute.
    • State-funded buildings not wholly owned by the state are subject to state plan review and inspection when the governmental subdivision has not adopted the listed codes or does not perform inspections; otherwise they must comply with the local codes and inspections.
    • For ordinary privately owned construction, inspection administration is governed by the applicable local law or ordinance.
    “All newly constructed buildings or structures subject to the state building code, including any addition, but excluding any renovation or repair of such a building or structure, owned by the state or an agency of the state, except as provided in subsection 2, shall be subject to a plan review and inspection by the commissioner or an independent building inspector appointed by the commissioner.”
  • Certificate of occupancyLimited

    Certificates of occupancy or use for buildings subject to Iowa's State Building Code and certificates approving specified buildings, facilities, or installations for licensure.

    • A local building department issues certificates of occupancy or use when required by ordinance.
    • When issued for a building constructed under the state building code, the certificate must certify conformity with the code and is in the form prescribed by the governing body of the governmental subdivision.
    • For facilities governed by Iowa Administrative Code chapter 481.280, if a certificate of occupancy is required for use, it will not be issued until the inspection fee is paid.
    • Chapter 481.280.5 applies to a certificate approving a building, facility, or installation for occupancy upon request from an owner or owner's agency when applicable rules are satisfied and all fees are paid.
    • The state sources do not require a certificate of occupancy for every building statewide.

    additional reinspection fee: 125 USD (Applies for each additional reinspection after the initial reinspection when original deficiencies remain uncorrected.)

    “Issue certificates of occupancy or use, permits, licenses, and other documents in connection with the construction of buildings or structures as may be required by ordinance. (1) A certificate of occupancy or use for a building or structure constructed in accordance with the provisions of the state building code shall certify that the building or structure conforms to the requirements of the code. The certificate shall be in the form the governing body of the governmental subdivision prescribes.”
  • Manufactured homesAllowed (with conditions)

    Placement and residential occupancy of manufactured homes under county zoning statewide in Iowa

    • A county may not disallow the proposed residential structure solely because it is a manufactured home.
    • The home must be located and installed under the same standards applicable to a site-built single-family dwelling on the same lot, including permanent foundation, setback, and minimum square footage standards.
    • The home must be assessed and taxed as a site-built dwelling.
    • A county may not require an incompatible perimeter foundation system and may not require more than one permanent foundation system.
    • Outside a manufactured home community or mobile home park, requirements may ensure visual compatibility of the permanent foundation system with surrounding residential structures.
    • Recorded restrictive covenants are not abrogated.
    • Counties may regulate transportation, water, sewerage, and other land development; the statute also bars width standards greater than twenty-four feet and certain design standards when federal standards are met.

    maximum mandated width standard: <= 24 feet (if the housing otherwise complies with 42 U.S.C. §5403)

    “A county shall not adopt or enforce zoning regulations or other ordinances which disallow the plans and specifications of a proposed residential structure solely because the proposed structure is a manufactured home. However, a zoning ordinance or regulation shall require that a manufactured home be located and installed according to the same standards, including but not limited to a permanent foundation system, set-back, and minimum square footage, which would apply to a site-built, single family dwelling on the same lot, and shall require that the home is assessed and taxed as a site-built dwelling.”
  • Accessory dwellingsAllowed (with conditions)

    City regulation of accessory dwelling units statewide in Iowa, within a zoning district where a single-family residence is an allowed principal use

    • At least one accessory dwelling unit must be allowed on the same lot as a single-family residence.
    • The accessory dwelling unit must comply with applicable building regulations under chapter 103A.
    • The unit may not exceed 1,000 square feet or 50 percent of the size of the single-family residence, whichever is larger; unfinished basements are excluded from the size calculation.
    • Historic-building-code restrictions, deed restrictions, and common-interest-community rules may limit or prohibit construction or use.
    • A manufactured or mobile home used as the accessory dwelling unit must be converted to real property by placement on a permanent foundation and assessed for real-estate taxes under section 435.26.
    • A historic-preservation area may regulate the unit to the extent the city or commission determines it incongruous and records its reasons.
    • Effective July 1, 2026.

    maximum accessory dwelling unit size: 1,000 square feet or 50% of the single-family residence, whichever is larger (unfinished basements excluded from the size calculation)

    “A city shall allow a minimum of one accessory dwelling unit on the same lot as a single family residence within a zoning district where a single family residence is an allowed principal use, in accordance with the following conditions:”
    One more reviewed finding on this topic
    • Allowed (with conditions) — County regulation of accessory dwelling units statewide in Iowa, within a zoning district where a single-family residence is an allowed principal use
      “A county shall allow a minimum of one accessory dwelling unit on the same lot as a single family residence within a zoning district where a single family residence is an allowed principal use, in accordance with the following conditions:”
  • Septic inspectionRequired

    Private sewage disposal systems serving buildings with one through four dwelling units, before qualifying ownership transfers statewide.

    • Inspection is required before transfer of ownership, including seller-financed real estate contracts.
    • The county recorder may not record the deed or conveyance document without a certified inspector report, unless weather or temporary physical conditions prevent inspection and the buyer executes a binding acknowledgment.
    • The requirement applies to sale, exchange, real estate contract, or other purchase of real estate and improvements.
    • Exceptions include specified court-ordered, foreclosure-related, fiduciary, family, demolition, recently installed system, partition, tax-sale, low-consideration, and qualifying family-entity transfers.
    • The septic tank must be opened and pumped at inspection, unless evidence shows it was properly pumped within three years before inspection by a licensed commercial septic tank cleaner.
    • A failing system must be renovated; a properly treating system without an unsanitary condition need not meet current construction standards.
    • Only a department-certified inspector may conduct the inspection.
    • An inspection is valid for two years for ownership transfers during that period.

    dwelling units: 1-4 · inspection validity: 2 years (for ownership transfers during that period) · prior septic pumping evidence: <= 3 years (must be by a department-licensed commercial septic tank cleaner) · civil penalty for fraudulent report: 5000 USD (and certification suspension for one year)

    “If a building where a person resides, congregates, or is employed is served by a private sewage disposal system, the sewage disposal system serving the building shall be inspected prior to any transfer of ownership of the building.”
  • Permit feesPublished

    Fees imposed and collected by Iowa state agencies, including any state-agency permit fees listed on the Iowa Government Fees Website.

    • The website does not include fees for universities or community colleges, open record requests, or costs for purchase of a product or good.
    • This claim does not establish local county or municipal permit-fee schedules.
    “Fees Imposed & Collected by State Agencies”
  • county zoning authorityGeneral

    Iowa counties may adopt zoning ordinances for land and structures within the county but outside the corporate limits of any city.

    • Chapter 335 applies to any Iowa county at the option of its board of supervisors.
    • The zoning power is subject to Iowa Code section 335.2: ordinances generally do not apply to agricultural land, farm houses, farm barns, farm outbuildings, or other structures primarily adapted for agricultural purposes while so used, except that ordinances may apply to structures, buildings, dams, obstructions, deposits, or excavations in or on river or stream floodplains.
    • A county may not require an application, approval, or fee for an ordinance to be deemed inapplicable to qualifying agricultural land or structures.
    • A county may not regulate, restrict, or prohibit the location of permanent buildings or temporary structures used for consumer-fireworks sales pursuant to section 10A.519 in locations zoned commercial or industrial.
    • The board of supervisors may divide the county into zoning districts, and regulations may differ among districts.
    • Regulations and restrictions require public-hearing and notice procedures under sections 335.6 and 331.305; district boundaries must identify the affected township and section and, if possible, streets or roads.
    • Energy-conservation and solar-access objectives do not require zoning in a county that did not have zoning before July 1, 1981.
    “applicable to any county [...] at the option of the board of supervisors [...] outside of the corporate limits of any city.”

Still unanswered

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

  • Zoning districts — Current zoning-district publication for unincorporated Washington County.
  • Living in an RV — Long-term or residential occupancy of recreational vehicles on private land throughout Washington County, including the unincorporated area.
  • Camping on your land — Temporary camping on private land throughout Washington County, including the unincorporated area.
  • Tiny homes — Occupancy of tiny homes on private land throughout Washington County, including the unincorporated area.
  • Short-term rentals — Short-term rentals in Washington County, Iowa, including unincorporated county areas.

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 Washington County, Iowa

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

Washington County scores 64/100 on the Bolthole Index, a strong county profile. Its strengths: low administrative friction for a quiet rural property and higher long-term carry cost.

Do you need a building permit in Washington County, Iowa?

Washington County does not require a county building permit for a home in unincorporated areas, and it has no county-wide zoning. Onsite septic is permitted by Washington County Environmental Health Department. 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 Washington County, Iowa?

Land in Washington County runs about $9,552 per acre, based on the latest county data.

What is the water situation in Washington County?

Washington County gets about 38" of rain a year, with severe drought in roughly 11.8% of years.

How remote is Washington County?

A representative private-land location has about 31,320 people within a 30-minute drive and 1,560,861 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 Washington County means bringing your own water and power. The kit we’d start with:

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How Washington compares in Iowa

Compare side-by-side →See all 99 Iowa counties ranked →