Summit County · 8,292 residents
Park City ADU rules
Park City: internal ADUs allowed (lot 6,000+ sq ft); detached ADUs allowed (lot 3,750+ sq ft). Owner occupancy applies.
Internal ADU (inside the home)
Detached ADU (backyard building)
✓ Checked against city sources on September 24, 2026 See sources
Park City 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. An Internal Accessory Dwelling Unit is allowed on a lot of 6,000 sq ft or more that has one single-family home. | 3,750 sq ft. Park City calls a separate backyard unit a Detached Accessory Apartment; it is allowed on lots of 3,750 sq ft or more, except in the Holiday Ranchettes Subdivision. |
| Owner occupancy | The owner must live in the single-family home, and only one of the two units may be rented; a deed restriction (Notice to Purchaser) is recorded with the County. | Not yet verified — confirm with the city |
| Parking | One parking space for the internal ADU in addition to the home's requirement; it may be uncovered and, in limited cases, tandem. | One parking space per bedroom in addition to the home's requirement; parking only in approved garages or paved driveways, with tandem allowed in limited cases. |
| Size limits | Not yet verified — confirm with the city | 280 to 1,000 sq ft, no more than one-third of the home's size, and no more than two bedrooms. |
| Height | Not yet verified — confirm with the city | Up to 18 ft above existing grade. |
| Setbacks | Not yet verified — confirm with the city | Must meet the zone's setbacks for single-family homes and any more restrictive disturbance limits on the recorded plat. |
| Zones | Allowed use in most residential districts (for example HR-1, Estate and Single Family); historic homes on the Historic Sites Inventory need an administrative conditional use permit. | Accessory Apartments are an allowed use (by administrative permit) in most zoning districts, including HR-1, Estate and Single Family; detached units are barred in Holiday Ranchettes Subdivision. |
| Short-term rentals | Neither the home nor the internal ADU may be rented for less than 30 days. | Nightly rentals are prohibited; the accessory apartment must be rented for at least 90 days. |
| Permit process | Administrative permit from the Planning Department with floor plan, elevations and site plan; homeowner-association notice is required. | Administrative permit reviewed and approved by the Planning Department (no public hearing), with floor plan, elevations, site plan and HOA notice; a deed restriction is recorded with the County. |
What the Park City council decided
Recorded votes and actions on ADU rules, linked to the public meeting record on OpenUtah.
· City Council
Approved Ord. 2026-19 amending the LMC (condo plat review to staff, S.B. 284 procedural alignment for planning commissioners, appeals and business licenses, TIS/TDM, historic-district fences); did not change ADU/accessory apartment rules
Read the meeting record
Proposed or pending changes
Not adopted as of September 24, 2026. They do not change the rules above until the city adopts them.
- Aug. 2026 staff report: 'Senate Bill 284 also requires updates to Accessory Dwelling Units, which take effect in October. The Planning Commission is continuing to review potential updates to the LMC as part of the affordable housing LMC updates.' No ADU amendment adopted as of 2026-09-24.
- After Oct. 1, 2026, Utah Code 10-21-304 requires a detached ADU to be permitted on any single-family lot of 11,000 sq ft or more; Park City's current bar on detached accessory apartments in Holiday Ranchettes Subdivision may need revision for lots of that size.
State law: detached ADUs from October 1, 2026
Park City 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 Park City 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; Park City makes the decision.
- The statewide map screen starts a new external ADU at about 11,000 sq ft. Park City's researched external minimum is 3,750 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 Park City 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 Park City before you apply.
- Park City — LMC Updates & Code Amendments
Lists 2026 LMC amendments, including Ord. 2026-19 (Aug. 13, 2026) aligning procedural items with S.B. 284.
- Utah S.B. 284 (2026) enrolled — Utah Code 10-21-304
Statewide detached-ADU rules effective Oct. 1, 2026.
- U.S. Census Bureau Vintage 2024 Utah city population estimates
2024 population 8,292 (8,278 in Summit County, 14 in Wasatch County); Summit County 43,109.
- Utah Code 10-2-301 — classification of municipalities
1,000-9,999 = fifth class.
- Utah Code 17-50-501 — classification of counties (superseded 2021 text)
31,000-124,999 = third-class county; confirm against the current recodified section.
- Official Park City website
Common Park City ADU questions
Can you build an ADU in Park City?
Park City: internal ADUs allowed (lot 6,000+ sq ft); detached ADUs allowed (lot 3,750+ sq ft). Owner occupancy applies. This is planning guidance, not a permit. Confirm the zone on your parcel with Park City.
What lot size does Park City require for an ADU?
Internal ADU: 6,000 sq ft minimum. An Internal Accessory Dwelling Unit is allowed on a lot of 6,000 sq ft or more that has one single-family home. Detached ADU: 3,750 sq ft minimum. Park City calls a separate backyard unit a Detached Accessory Apartment; it is allowed on lots of 3,750 sq ft or more, except in the Holiday Ranchettes Subdivision.
Does Park City require the owner to live on the property?
Internal ADU: The owner must live in the single-family home, and only one of the two units may be rented; a deed restriction (Notice to Purchaser) is recorded with the County. Detached ADU: Not yet verified — confirm with the city.
How much parking does a Park City ADU need?
Internal ADU: One parking space for the internal ADU in addition to the home's requirement; it may be uncovered and, in limited cases, tandem. Detached ADU: One parking space per bedroom in addition to the home's requirement; parking only in approved garages or paved driveways, with tandem allowed in limited cases.
Can an ADU in Park City be a short-term rental?
Internal ADU: Neither the home nor the internal ADU may be rented for less than 30 days. Detached ADU: Nightly rentals are prohibited; the accessory apartment must be rented for at least 90 days.
What does it cost to build an ADU in Park City?
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 Park City?
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 Park City 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 Park City 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.