Salt Lake County · Service area

Can you build a backyard home in Cottonwood Heights?

Today a detached ADU here is a conditional use. On October 1 that becomes illegal.

Conditional use today The statute prohibits exactly this.

Takes about 3 minutes. No email required to see your result.

What changes here on October 1

Today a detached ADU here is a conditional use. On October 1 that becomes illegal.

Cottonwood Heights currently allows internal ADUs as a permitted use but routes detached ADUs through a conditional use process in its R-1, RR-1 and F-1 zones. Section 10-21-304 expressly bars a city from requiring a conditional use permit for a detached ADU in a primarily residential zone. This is one of the clearest before-and-after changes on the Wasatch Front.

“A specified municipality shall adopt a land use regulation that permits a detached accessory dwelling unit on any lot or parcel that is 11,000 square feet or larger…” — S.B. 284, Enrolled Copy, Utah Code § 10-21-304, effective October 1, 2026.

The numbers that decide your project

Cottonwood Heights ADU rules at a glance

Rule	Cottonwood Heights — Cottonwood Heights 19.75
Detached ADUs today	Conditional use in R-1, RR-1 and F-1 zones — discretionary approval required. confirm with city
Detached ADUs from Oct 1	Conditional use permit prohibited for a qualifying detached ADU in a primarily residential zone. state law
Internal ADUs	Permitted use on lots of 6,000 sq ft or more in R-1, RR-1 and F-1. confirm with city
Owner occupancy	Record owner must occupy either the primary dwelling or the ADU as a permanent residence, with proof at application. confirm with city
Parking	One additional non-tandem stall per ADU, on top of the two off-street stalls every single-family property must have. confirm with city
Short-term rental	Prohibited under 19.75.050.B. confirm with city

state law Quoted from the enrolled copy of S.B. 284 — primary source, verified.
confirm with city From the city's published ADU material or council reporting — Arena confirms at the planning counter before design.
moving now The city is actively amending this ahead of October 1, 2026. Treat as a moving target.
We would rather show you the gap than guess. Arena is a builder, not a law firm — confirm your parcel with Cottonwood Heights before you sign anything.

What that means on your lot

If you were quoted a conditional use process in Cottonwood Heights this year, get a second answer after October 1.

Is my Cottonwood Heights lot 11,000 sq ft?

That single number decides whether the new state law applies to you. Enter your address above — we'll tell you which rule you fall under and which plans fit, in about three minutes.

Fixed price, Cottonwood Heights-wide

Arena publishes every price — seven plans from The Lookout at 735 sq ft to The Launchpad at 2,541 sq ft. One team owns design, engineering, permitting and construction.

From $128,625 · see every price →

Can you build a backyard home in Cottonwood Heights?

Today a detached ADU here is a conditional use. On October 1 that becomes illegal.

Cottonwood Heights ADU rules at a glance

If you were quoted a conditional use process in Cottonwood Heights this year, get a second answer after October 1.

Is my Cottonwood Heights lot 11,000 sq ft?

Fixed price, Cottonwood Heights-wide

Three places to start

The Lookout

The Loft

The Uptown

There's still $2,200 a month hiding in your house.