Building permits, zoning and land rules in Washington County, Utah

Yes. Construction in Washington County's county-regulated jurisdiction may not begin until the building inspector issues a written building permit¹. Community Development reviews plans, issues building permits and inspects structures through construction⁵. The statewide construction standards include the 2024 International Building Code and the 2021 International Residential Code, with applicable amendments¹¹. Building-permit fees are based on project valuation and carry a 1% state surcharge¹². Washington County accepts building-permit applications only through its online permitting system¹³. An agricultural structure may qualify for an exemption only on more than 2 acres in specified unincorporated zones, and the statewide exemption is limited to structures used solely for agriculture and not for human occupancy^14,15.

Washington County Community Development issues building permits, reviews plans and inspects construction through every phase in the county's jurisdiction⁵. Planning & Zoning and Building merged into Community Development, so the same counter is the starting point for a building-permit or zoning question⁵. Community Development also administers subdivision regulations⁵. A preliminary plat must comply with applicable local, state and federal law and pass staff review before moving forward¹⁶. Ask Community Development about floodplain development approval before starting mapped-floodplain work, and direct county road or driveway-access questions to Public Works^5,17.

Yes. Washington County administers zoning for unincorporated land, while incorporated cities and towns control their own planning and development^2,3. Minimum lot area is district-specific: A-5 requires 5 acres, RA-1 requires 1 acre and R-1-10 requires 10,000 square feet². Setbacks are district-specific too; RA-1 uses a 25-foot front setback and 10-foot side and rear setbacks, while RA-2.5 uses 25 feet on each side². Accessory dwelling units have a 25-foot minimum setback on all sides¹⁸. The cited open-space and agricultural districts have a 35-foot height limit². The MH district recognizes manufactured homes at up to 6 units per acre, while Pine Valley manufactured housing needs at least 1,400 square feet of living area^2,10.

Wastewater must go to a public sewer or an onsite wastewater system, so off-grid land is not exempt from an approved sanitation route⁴. The Southwest Utah Public Health Department reviews plans, issues septic permits, conducts inspections and keeps septic-system records in its district⁴. Before installing, replacing or modifying a septic system, obtain a permit and approved design⁴. Washington County septic review also requires approval from the Washington County Water Conservancy District or Ash Creek Special Service District⁴. Only about 11% of county soils rate without severe limits for a conventional drain field, so test the site before relying on a conventional system⁶. The health department must inspect the system before backfilling¹⁹.

We could not confirm a general rule allowing temporary RV camping on private land in unincorporated Washington County; ask Community Development about the parcel and proposed duration. An RV park may be approved only as a conditional use in the MH zoning district, but that rule does not authorize living in a single RV on private land⁹. Utah's separate RV-park health rule also does not answer private-land occupancy²⁰. Washington County defines a Tiny Home on Foundation as a dwelling from 150 through 1,000 square feet, but the definition does not establish where residential occupancy is allowed⁹. We could not confirm the current parcel-specific approval path for occupying a tiny home; ask Community Development before purchase. Manufactured homes are recognized in the MH district, and Pine Valley applies a 1,400-square-foot living-area minimum to manufactured housing^2,10. Any occupied off-grid setup still needs public sewer or an approved onsite wastewater system⁴.

1. Confirm the parcel's jurisdiction, zoning district, minimum lot area, setbacks and height with Community Development before designing^2,5.
2. If dividing land, complete preliminary-plat review before treating proposed lots as buildable¹⁶.
3. Plan driveway access under county standards; adjacent developments may have to share access^5,21.
4. Confirm public sewer service or obtain an approved design, septic permit and required district sign-off⁴.
5. For a well, secure the water right and Start Card before construction and use a licensed driller⁸.
6. Apply electronically and receive the written county building permit before work begins^1,13.
7. Complete required inspections; when a third-party inspection firm completes an inspection and submits its report, state law directs the local regulator to issue the certificate of occupancy²².

Confirm the parcel's jurisdiction, zoning district, minimum area, setbacks and height with Community Development before deciding it is buildable^2,5. Check whether the parcel is a legal lot because county review considers its creation date, zoning area and approved access¹⁸. Check the floodplain map because mapped-floodplain work requires approval before construction starts¹⁷. About 77% of Washington County is federal land, so verify boundaries before assuming neighboring ground is privately buildable⁶. Run septic testing early because only 11% of county soils rate without severe limits for a conventional drain field⁶. A typical county home carries about a 0.4% effective property-tax rate and a $2,076 annual bill⁶.