Building permits, zoning and land rules in San Juan County, Utah

Utah law requires building-permit approval for covered construction, reconstruction, alterations and changes of use outside cities and towns¹. San Juan County will not issue a building permit unless plans comply with its Fire Policy; a permit that later fails to comply becomes void, and no certificate of occupancy will issue². The Fire Policy applies to private and county-owned land in unincorporated San Juan County, excluding land under sole State, Federal or Tribal jurisdiction; government ownership alone does not establish that exclusion².

San Juan County follows Utah's adopted building, construction and fire codes¹⁴. Owner-builder licensing exemptions leave building-permit requirements in place, while qualifying agricultural structures have a separate state construction-code exception with location and utility-work conditions^11,15. Greenbelt is a property-tax program, not proof of a building or zoning exemption¹⁶.

The San Juan County Planning & Building Department handles building, subdivision and conditional-use permit applications⁹. The department is at 117 S. Main Street in Monticello and can be reached at 435-587-3829 or permits@sanjuancountyut.gov⁹.

Inside Bluff, the town handles building permits; septic permits still come from San Juan Public Health^4,6.

The published building-permit fee is 1.75 times the square footage; the county gives a 2,000-square-foot example of $3,500⁹. Inspections cost $65 each plus the state mileage rate, and work performed without a permit costs twice the permit price, plus $150 per week when work continues beyond a 30-day notice⁹. We could not confirm a complete current building-permit application sequence; ask Planning & Building which plans, approvals and inspection stages apply⁹. Dividing unincorporated land requires a subdivision permit through the county application portal¹⁷.

San Juan County zoning governs unincorporated parcels according to their district³. Bluff administers its own zoning inside town limits, while San Juan Public Health continues to handle septic permits there^5,6. The county tells applicants to identify the parcel's zone before determining whether a use is permitted or needs a conditional-use permit, but its proposed 2025 use table is tabled rather than operative¹⁸.

Spanish Valley includes Spanish Valley Residential and Spanish Valley Highway Commercial districts, planned-community districts and an overnight-accommodations overlay, but that is not a complete countywide district list¹⁹. Short-term rentals are prohibited in the Spanish Valley Residential District³. In the Spanish Valley Highway Commercial District, every building and lot must directly access a public street or frontage road and provide safe access for service, fire protection and parking²⁰. In the MU-1, A-1 and RR-1 districts, the baseline minimum lot area for a main use is 1 acre, though lots as small as 0.25 acre are possible with municipal water or sewer or a written Health Department opinion²¹. Those districts require main buildings to sit 25 feet from the front and rear lot lines and 15 feet from side lot lines, with a 30-foot side setback on corner lots²². Ask Planning & Building for the operative zone, setbacks and use rules before designing around the tabled proposal⁹.

San Juan Public Health permits and inspects every septic wastewater system in San Juan County and maintains system records for residents⁶. The reviewed permit fee is $440 plus mileage, and the reviewed recertification fee is $78 plus mileage⁶. Call 435-587-3838 to ask about an application or inspection⁶.

Only 19.2% of mapped county soils avoid a “very limited” rating for conventional septic drain fields, so a successful conventional layout should not be assumed from acreage alone²³. Utah's statewide onsite-wastewater rules are administered locally and allow local health departments to impose stricter requirements²⁴. San Juan County adopted a replacement subdivision ordinance in 2024; ask Planning & Building and San Juan Public Health which sewer-connection and private-system conditions apply before relying on a subdivision lot for off-grid living^6,9,17.

We could not confirm an adopted San Juan County rule that generally allows temporary or long-term RV occupancy on private land, so ask Planning & Building about the parcel, duration, utilities and zone before moving in⁹. Utah's RV-park rule governs temporary quarters in an RV park, not a blanket right to occupy an RV on private acreage⁸.

A tiny house in a Utah RV park must meet state certification or inspection conditions; outside a park, permission depends on local land-use rules and the unit's classification⁸. We could not confirm a general San Juan County tiny-home occupancy rule; ask Planning & Building how the proposed unit is classified⁹. A county option for one additional dwelling for an employee, seasonal worker or immediate family member requires at least one-half acre per unit plus Planning Commission and Board of Health approval in MU-1, A-1 and RR-1¹³. An occupied mobile home, including certain modular or prefabricated units not on permanent foundations, must have at least 500 square feet of enclosed usable area, adequate foundation and skirting, and a separate lot meeting its district requirements^10,13. The mobile-home provision does not establish a minimum floor area for every dwelling type¹⁰. San Juan County prohibits placing or relocating manufactured homes built before the federal standards took effect on June 15, 1976¹³.

1. Ask Planning & Building to identify the governing jurisdiction, parcel zone, allowed residential use and required land-use approvals^3,7,9.
2. Confirm legal access; a new state-highway connection, land-use change or intensified access requires a UDOT conditional access permit for plan review and an encroachment permit for construction in the highway right-of-way²⁵.
3. Secure a lawful water source; a new well requires a valid water right and an approved Start Card before construction¹².
4. Have San Juan Public Health approve the septic plan before construction when sewer is unavailable^6,26.
5. Submit plans to Planning & Building, including what is needed to demonstrate compliance with the county Fire Policy, and confirm fees and inspections^2,9.
6. Ask Planning & Building which inspections and occupancy approvals the project needs; Fire Policy noncompliance voids an issued permit and blocks a certificate of occupancy^2,9.

Start with water, wastewater, legal access, zoning and flood constraints rather than assuming a large tract is buildable³. A well needs a valid water right and state permission¹². For subdivision lots, ask Planning & Building about utility requirements under the replacement subdivision ordinance before budgeting for a private well or septic system^9,17. In the Spanish Valley Residential and Highway Commercial districts, land within the 100-year floodplain must be identified on plats and left free of buildings and impervious surfaces²⁰.

Only 19.2% of mapped county soils avoid a “very limited” rating for conventional septic drain fields, so obtain a site evaluation before relying on a conventional system²³. San Juan County receives about 10.2 inches of precipitation a year, and severe drought has affected 37.3% of measured years, making a verified water source especially important²³. Federal land accounts for 64.8% of county acreage, so verify legal access across every intervening parcel²³.