Washington County · 8,722 residents
Santa Clara ADU rules
Santa Clara: internal ADUs allowed (lot 6,000+ sq ft); detached ADUs allowed (lot 6,000+ sq ft). Owner occupancy applies.
Internal ADU (inside the home)
Detached ADU (backyard building)
✓ Checked against city sources on September 24, 2026 See sources
Santa Clara ADU rules at a glance
| Rule | Internal ADU (basement, attic, inside the home) | Detached ADU (backyard building) |
|---|---|---|
| Allowed? | Allowed | Allowed |
| Minimum lot | 6,000 sq ft. Your lot must generally be at least 6,000 sq ft for an internal ADU. | 6,000 sq ft. Santa Clara allows an ADU on residential lots of at least 6,000 sq ft, which is smaller than the 11,000 sq ft statewide minimum that takes effect Oct 1, 2026. |
| Owner occupancy | The owner must live in the main home. | The owner must live in either the main home or the ADU. |
| Parking | One off-street space for the internal unit, in addition to the home's required parking. | One additional off-street parking space is required. |
| Size limits | The unit must be entirely within the footprint of the home and share its power and water meters; one internal or detached ADU per property. | Up to 1,000 sq ft or 30% of the main home's footprint (not counting the garage), whichever is greater; one ADU or internal ADU per property. It can be built over an attached or detached garage if the parking below stays parking. |
| Height | Not yet verified — confirm with the city | Cannot exceed the zone's height limit for accessory structures unless it is attached to the main home. |
| Setbacks | Not yet verified — confirm with the city | May be in the front, side or rear yard if it meets the main home's setback requirements. |
| Zones | Permitted in all residential zones. | Permitted in residential zones. |
| Short-term rentals | Must be rented for 30 consecutive days or more; short-term rentals are not allowed. | Must be rented for 30 consecutive days or more; short-term rentals are not allowed. |
| Permit process | File an Internal ADU Permitted Use Application ($100 fee, waived if the unit is part of a new home's plans) with a building permit; the city inspects before issuing the permit and may inspect once a year. A business license is required, renewed yearly, if the unit is rented. | Permitted use; a building permit is required, and the ADU cannot be built until the main home's building permit has been issued. |
Proposed or pending changes
Not adopted as of September 24, 2026. They do not change the rules above until the city adopts them.
- June 11, 2026: Planning Commission public hearing on updates to Chapter 17.22 (ADUs) and residential zone chapters for LUDMA compliance. The codified 17.22.030 now cites Ord. 2026-12, so the ADU changes appear adopted; the adoption date was not found.
State law: detached ADUs from October 1, 2026
Santa Clara 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 Santa Clara 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; Santa Clara makes the decision.
- The statewide map screen starts a new external ADU at about 11,000 sq ft. Santa Clara's researched external minimum is 6,000 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 Santa Clara 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.
Sources
We link only to government sources and public meeting records. Codes change; confirm the current version with Santa Clara before you apply.
- Santa Clara City — Internal Accessory Dwelling Unit (IADU) Permitted Use Application (Aug 2025)
IADU requirements, $100 fee, 1 extra parking space, 30-day minimum rental
- Santa Clara City — Accessory Dwelling Unit (ADU) Conditional Use Application (March 2024)
Detached/attached ADU checklist, $100 fee, 1 extra space, 30-day minimum rental (describes the pre-2026 administrative conditional use process)
- Santa Clara City — Notice of Public Hearing: Proposed City Code Updates, June 11, 2026
Planning Commission hearing on Chapter 17.22 Accessory Dwelling Units and related chapters for LUDMA compliance
- Santa Clara City — Forms and Applications
Lists the current IADU application
- U.S. Census Bureau — Utah subcounty population estimates, Vintage 2025 (sub-est2025_49.csv)
July 1, 2025 population estimates for Utah cities and counties
- Utah S.B. 284 (2026) enrolled — Local Land Use Modifications
Enacts Utah Code 10-21-304 (detached ADUs on lots of 11,000 sq ft or more in specified municipalities, effective Oct 1, 2026) and the 'specified municipality' definition
- Utah Code Title 17, Chapter 60 (county classification, 17-60-104/105)
Current county class population thresholds: 3rd class 40,000-259,999; 4th class 12,000-39,999
- Official Santa Clara website
Common Santa Clara ADU questions
Can you build an ADU in Santa Clara?
Santa Clara: internal ADUs allowed (lot 6,000+ sq ft); detached ADUs allowed (lot 6,000+ sq ft). Owner occupancy applies. This is planning guidance, not a permit. Confirm the zone on your parcel with Santa Clara.
What lot size does Santa Clara require for an ADU?
Internal ADU: 6,000 sq ft minimum. Your lot must generally be at least 6,000 sq ft for an internal ADU. Detached ADU: 6,000 sq ft minimum. Santa Clara allows an ADU on residential lots of at least 6,000 sq ft, which is smaller than the 11,000 sq ft statewide minimum that takes effect Oct 1, 2026.
Does Santa Clara require the owner to live on the property?
Internal ADU: The owner must live in the main home. Detached ADU: The owner must live in either the main home or the ADU.
How much parking does a Santa Clara ADU need?
Internal ADU: One off-street space for the internal unit, in addition to the home's required parking. Detached ADU: One additional off-street parking space is required.
Can an ADU in Santa Clara be a short-term rental?
Internal ADU: Must be rented for 30 consecutive days or more; short-term rentals are not allowed. Detached ADU: Must be rented for 30 consecutive days or more; short-term rentals are not allowed.
What does it cost to build an ADU in Santa Clara?
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 Santa Clara?
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 Santa Clara 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 Santa Clara 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 (2025). Editorial standards.