Utah County · 10,393 residents
Salem ADU rules
Salem: internal ADUs allowed (lot 6,000+ sq ft); detached ADUs allowed (lot 11,000+ sq ft).
Internal ADU (inside the home)
Detached ADU (backyard building)
Not yet fully verified · last reviewed September 7, 2026 See sources
Salem 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. >=6,000 sq ft in residential zones | 11,000 sq ft. Local code amended Feb 18, 2026 to reduce minimum from 2 acres to 1 acre. SB 284 statewide by-right floor >=11,000 sq ft operative 2026-10-01 will require further reduction for specified municipalities — confirm whether 1-acre minimum has been updated again |
| Parking | One off-street parking space for the ADU | Not yet verified — confirm with the city |
| Setbacks | Not yet verified — confirm with the city | Access from the lot of the main dwelling or recorded easement meeting fire code; design coordination with main structure was debated |
| Zones | Permitted use in residential zones meeting lot-size threshold (Title 14 §14-1-065) | Residential zones under §14-1-065 (detached allowed as local option beyond internal mandate) |
| Permit process | Contact Planning & Zoning; ADU may not be in a mobile home; utilities shared with main dwelling; cannot subdivide/sell separately | Shared utilities with primary; 30+ day rentals; Planning & Zoning application |
State law: detached ADUs from October 1, 2026
Salem 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 Salem 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; Salem makes the decision.
- "Likely" above 15,000 sq ft is this site's planning band for a large recorded lot. It is not a sentence in the Salem 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.
Planning notes for Salem
Salem held a 2026 proceeding specifically to update detached-ADU rules for SB284. A backyard proposal deserves a fresh review of the resulting ordinance instead of relying only on earlier guidance. We can help compare an internal option with a detached concept and establish which standards govern your application date.
Bring these to your review
- Desired unit type and timing
- Site plan with house, proposed unit and parking
- Any prior ADU permits
The question to resolve first
What final detached-ADU ordinance applies, and when can your application use it?
Sources
We link only to government sources and public meeting records. Codes change; confirm the current version with Salem before you apply.
- Salem detached-ADU hearing, May 6, 2026
Official hearing notice; final ordinance text and effective date need confirmation
- Utah S.B. 284 (2026), enrolled bill
Statewide detached-ADU requirements for specified municipalities, operative October 1, 2026.
- Official Salem website
Common Salem ADU questions
Can you build an ADU in Salem?
Salem: internal ADUs allowed (lot 6,000+ sq ft); detached ADUs allowed (lot 11,000+ sq ft). This is planning guidance, not a permit. Confirm the zone on your parcel with Salem.
What lot size does Salem require for an ADU?
Internal ADU: 6,000 sq ft minimum. >=6,000 sq ft in residential zones. Detached ADU: 11,000 sq ft minimum. Local code amended Feb 18, 2026 to reduce minimum from 2 acres to 1 acre. SB 284 statewide by-right floor >=11,000 sq ft operative 2026-10-01 will require further reduction for specified municipalities — confirm whether 1-acre minimum has been updated again.
How much parking does a Salem ADU need?
Internal ADU: One off-street parking space for the ADU. Detached ADU: Not yet verified — confirm with the city.
What does it cost to build an ADU in Salem?
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 Salem?
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 Salem 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 Salem 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: UGRC POPLASTESTIMATE / Census-derived municipal estimates (manual fill where UGRC blank). Editorial standards.