How Salt Lake City Handles Accessory Structures: A Practical Guide

Salt Lake City maintains 198 local ordinances across all categories, and 9 of those deal specifically with accessory structures. Here is a breakdown of what the city actually requires, what is prohibited, and where Salt Lake City falls on the strict-to-permissive spectrum compared to other cities.

Tiny Homes

Tiny homes on foundations treated as dwellings; tiny homes on wheels treated as RVs and not allowed as permanent residences.

Key details: Fact: Foundation tiny homes legal. Fact: IRC Appendix Q adopted. Fact: THOWs treated as RVs. Fact: Not for permanent occupancy on private lots. Fact: Can be used as ADU if on foundation.

Contact your local code enforcement office for specific penalty information.

Carport Rules

Carports allowed as accessory structures with standard setbacks; front-yard carports require special review.

Key details: Fact: Rear/side yard preferred. Fact: Front yard usually prohibited. Fact: 4 ft setback minimum. Fact: Building permit for permanent. Fact: Portable over 200 sq ft needs permit.

Contact your local code enforcement office for specific penalty information.

Garage Conversions

Garage conversions require building permit; replacement parking must be provided if required by zone.

Key details: Fact: Building permit required. Fact: Egress and insulation to code. Fact: Replacement parking if required. Fact: Can convert to ADU. Fact: Historic district HLC review.

Contact your local code enforcement office for specific penalty information.

ADU Impact Fees

ADUs in Salt Lake City pay the city's residential impact fees (parks, fire, police, transportation, water, sewer, stormwater) assessed under SLC Code Chapter 18.98, with exemption pathways available for affordable units under 18.98.060.

Key details: Governing Code: SLC Code Chapter 18.98; Utah Code Title 11, Chapter 36a. Fee Categories: Parks, fire, police, transportation, water, sewer, stormwater. Fee Schedule: Salt Lake City Consolidated Fee Schedule (annual ordinance). Exemption Path: SLC Code 18.98.060 for qualifying affordable units. Offsets Available: Yes, under SLC Code 18.98.070 for qualifying public improvements.

Failure to pay assessed impact fees prior to building permit issuance results in the permit being withheld. Attempting to occupy an ADU without satisfying impact fee obligations can result in a stop-work order, denial of certificate of occupancy, and lien against the property under Utah Code 11-36a.

ADU Permits

One ADU (internal, attached, or detached) is allowed by right on any lot containing a single-family dwelling under Salt Lake City Code 21A.40.200, in alignment with Utah HB 82 (2021). Building permits are required for all three configurations.

Key details: Governing Code: SLC Code 21A.40.200; Utah Code 10-9a-530 (HB 82, 2021). Permitted By Right: Yes — one ADU per single-family lot (internal, attached, or detached). Permits Required: Building permit; electrical, plumbing, mechanical for attached/detached. Max Detached Height: 17 ft base; up to 24 ft with added setbacks. Permit Portal: Accela Citizen Access (aca-prod.accela.com/SLCREF).

Building, occupying, or renting an ADU without required permits is a zoning and building code violation enforced by Salt Lake City Civil Enforcement. Penalties may include stop-work orders, mandatory permit retro-application with higher fees, daily civil penalties, and orders to vacate or remove unpermitted construction.

Salt Lake City is more permissive than most cities when it comes to adu permits. That said, there are still limits.

ADU Rental Restrictions

SLC Code 21A.40.200 expressly prohibits renting an ADU as a short-term rental. ADUs are restricted to long-term rentals of 30 consecutive days or longer; under Utah Code 10-9a-530 internal ADUs must be offered for rentals of 30 days or more.

Key details: Governing Code: SLC Code 21A.40.200; Utah Code 10-9a-530. Short-Term Rentals: Prohibited — explicit ban in 21A.40.200. Minimum Rental Term: 30 consecutive days or longer. STR Platform Listings: Not allowed (Airbnb, VRBO, etc.). Rent Caps: None — Utah preempts municipal rent control.

Listing or operating an ADU as a short-term rental violates SLC Code 21A.40.200 and is enforceable by SLC Civil Enforcement. Penalties include daily civil fines, cease-and-desist orders, revocation of any business license, and potential loss of by-right ADU status. Repeat or willful violations can be prosecuted as a Class B misdemeanor under Title 21A.

Compared to other cities, Salt Lake City takes a harder line on adu rental restrictions. The enforcement and penalty structure reflects that.

ADU Owner Occupancy

Per Utah Code 10-9a-530 (HB 82, 2021), Salt Lake City requires the property owner to occupy either the primary dwelling or the internal ADU as their principal residence. The owner-occupancy requirement can be enforced via affidavit.

Key details: Governing Code: SLC Code 21A.40.200; Utah Code 10-9a-530. Owner Occupancy Required: Yes — owner must occupy primary dwelling OR the ADU. Proof Method: Recorded owner-occupancy affidavit. Applies To: Internal ADUs by state law; also enforced for detached ADUs locally. Term Type: Principal place of residence (not seasonal).

Renting both the primary dwelling and the ADU to non-owner tenants violates SLC Code 21A.40.200 and Utah Code 10-9a-530. Enforcement is complaint-driven; remedies include cease-and-desist orders, civil penalties, and revocation of any ADU rental registration. Filing a false owner-occupancy affidavit may constitute a misdemeanor.

Shed Rules

Sheds under 200 sq ft and 12 ft tall exempt from building permit but must meet setbacks (SLC 21A.40).

Key details: Fact: 200 sq ft exempt from permit. Fact: 12 ft height limit for exempt sheds. Fact: 1 ft rear/side setback minimum. Fact: Behind front building line. Fact: Permit needed for utilities.

Contact your local code enforcement office for specific penalty information.

ADU Rules

ADUs (internal, attached, and detached) allowed citywide in single-family zones per SLC 21A.40.200 (2018, expanded 2021).

Key details: Fact: One ADU per single-family lot. Fact: Up to 650-720 sq ft detached. Fact: 17-23 ft height limit. Fact: Owner-occupancy required. Fact: One parking space (waived near transit).

Contact your local code enforcement office for specific penalty information.

Salt Lake City is more permissive than most cities when it comes to adu rules. That said, there are still limits.

The Bottom Line

Compared to many U.S. cities, Salt Lake City gives residents more room on accessory structures. 2 of the 9 rules here are rated permissive. But permissive does not mean unregulated. There are still requirements, and the city does enforce them when violations are reported.

These rules come from Salt Lake City's publicly available municipal code. For complete penalty schedules, exemption details, and answers to common questions, see the individual ordinance pages throughout this guide.