Tooele County · 40,919 residents

Tooele ADU rules

Tooele: internal ADUs allowed (lot 6,000+ sq ft); detached ADUs allowed (lot 8,500+ sq ft). Owner occupancy applies.

Internal ADU (inside the home)

Generally allowed

Detached ADU (backyard building)

Generally allowed

✓ Checked against city sources on September 24, 2026 See sources

Tooele ADU rules at a glance

Tooele internal and detached accessory dwelling unit rules
RuleInternal ADU (basement, attic, inside the home)Detached ADU (backyard building)
Allowed?AllowedAllowed
Minimum lot6,000 sq ft. Tooele requires a lot of at least 6,000 sq ft for an internal ADU.8,500 sq ft. Tooele allows detached ADUs on lots of 8,500 sq ft or more, which is already more permissive than the 11,000 sq ft statewide floor that starts Oct 1, 2026.
Owner occupancyThe owner of the main home must live in either the main home or the ADU.The owner of the main home must live in either the main home or the ADU.
ParkingOne additional on-site parking stall is required for an internal ADU, and ADU parking cannot sit in street-side front or side setbacks except on an approved driveway.One additional on-site parking stall is required per ADU bedroom (so one or two stalls, since ADUs are capped at two bedrooms).
Size limitsAn internal ADU must be at least 400 sq ft, no larger than the main home's foundation footprint, and may have no more than two bedrooms.A detached ADU must be between 800 and 1,200 sq ft with no more than two bedrooms.
HeightADU height is limited to the lower of the zone's height limit or the height of the main home.ADU height is limited to the lower of the zone's height limit or the height of the main home.
SetbacksADUs follow the front, side and rear setbacks of the underlying zone; entrances to internal ADUs must be on the side or rear of the home.Detached ADUs follow the zone's setbacks, must be at least 10 ft from the main home, and must sit behind the home (corner lots may place it to the side if it is flush with or behind the street-facing side of the house).
ZonesPermitted in all single-family zones (R1-7, R1-8, R1-10, R1-12, R1-14, R1-30, RR-1, RR-5, RR-20) and in the MU-B, MU-G and NC zones; conditional in GC and RC; prohibited in multi-family (MR) zones.Permitted in all single-family zones (R1-7 through R1-30, RR-1, RR-5, RR-20) and in the MU-B, MU-G and NC zones; detached ADUs are prohibited in GC, RC and multi-family (MR) zones.
Permit processA building permit identified as an ADU permit is required; no separate ADU registration or city business license is needed, and internal ADUs pay no impact fees.A building permit identified as an ADU permit is required (no separate registration or business license); detached ADUs pay 50% of the single-family water, sewer, public safety and parks impact fees and must match the main home's architecture, materials and colors.

State law: detached ADUs from October 1, 2026

Tooele is a “specified municipality” under Utah S.B. 284. Beginning October 1, 2026, it must permit one detached ADU as a permitted use on a lot of 11,000 sq ft or more that has a detached single-family home. The city can still apply setbacks, height, design, owner-occupancy and limited parking rules, and it may allow detached ADUs on smaller lots. How the state ADU laws work.

How our property map screens Tooele lots

The map colors parcels using the rules on this page and the recorded lot size. A color is a planning screen, not a permit; Tooele makes the decision.

  • The statewide map screen starts a new external ADU at about 11,000 sq ft. Tooele's researched external minimum is 8,500 sq ft. Lots below that city minimum stay highly unlikely on the map even when they clear 11,000 sq ft.
  • "Likely" above 15,000 sq ft is this site's planning band for a large recorded lot. It is not a sentence in the Tooele code. Owner occupancy, parking, setbacks, zones, and HOA rules below still have to be checked.

Planned communities, PRDs and PUDs

Reviewed on September 22, 2026 against this city's research file, its published ADU page where one was found, and Utah meeting packets. No adopted sentence was confirmed that allows or bans an ADU in every PUD, PRD, PRUD, or planned community. If the assessor class or subdivision name says PUD, PRD, PRUD, planned unit development, planned residential development, planned community, resort community, or master planned community, the map keeps that lot highly unlikely regardless of size. A plat, CC&Rs, or development agreement can still prohibit an ADU where the zone allows one.

Open Tooele on the property map

Sources

We link only to government sources and public meeting records. Codes change; confirm the current version with Tooele before you apply.

Common Tooele ADU questions

Can you build an ADU in Tooele?

Tooele: internal ADUs allowed (lot 6,000+ sq ft); detached ADUs allowed (lot 8,500+ sq ft). Owner occupancy applies. This is planning guidance, not a permit. Confirm the zone on your parcel with Tooele.

What lot size does Tooele require for an ADU?

Internal ADU: 6,000 sq ft minimum. Tooele requires a lot of at least 6,000 sq ft for an internal ADU. Detached ADU: 8,500 sq ft minimum. Tooele allows detached ADUs on lots of 8,500 sq ft or more, which is already more permissive than the 11,000 sq ft statewide floor that starts Oct 1, 2026.

Does Tooele require the owner to live on the property?

Internal ADU: The owner of the main home must live in either the main home or the ADU. Detached ADU: The owner of the main home must live in either the main home or the ADU.

How much parking does a Tooele ADU need?

Internal ADU: One additional on-site parking stall is required for an internal ADU, and ADU parking cannot sit in street-side front or side setbacks except on an approved driveway. Detached ADU: One additional on-site parking stall is required per ADU bedroom (so one or two stalls, since ADUs are capped at two bedrooms).

What does it cost to build an ADU in Tooele?

Wasatch Front planning bands are often about $55,000–$145,000 for an internal suite, $70,000–$175,000 for a garage conversion, and $95,000–$250,000 or more for a new detached unit, before unusual site work. These are planning ranges, not bids.

Can an HOA block an ADU in Tooele?

City approval does not override CC&Rs or plat notes. Read the HOA documents and your subdivision plat before you design. A private restriction can stop a unit the city would otherwise allow.

Before you design: general checks for any Utah ADU

General planning advice, not Tooele code.

  • Confirm the zoning district on the city zoning map. The county assessor’s “residential” class is not zoning.
  • Read your HOA CC&Rs and subdivision plat notes; private restrictions can block a unit the city allows.
  • Sketch existing and proposed parking. Driveway geometry and access often decide what fits.
  • Ask early about sewer, water and electrical capacity; utilities can force a redesign.
  • Expanding a building’s footprint usually triggers full setback and height rules.

Nearby city ADU rules

Want to know what fits on your Tooele lot?

Free, no obligation. We review your parcel against these rules and, if you want, introduce independent design and construction partners. Partners may pay us for referrals.

Utah ADU Builder provides educational planning guidance. This page is not legal advice and not a permit. Population: U.S. Census Bureau population estimate (2024). Editorial standards.