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Cottonwood Heights Journal

Accessory dwelling units now legal

Nov 22, 2021 10:31AM ● By Cassie Goff

The state legislature addressed internal ADUs this past May but has not yet regulated external ADUs. (Mike Johnson/Cottonwood Heights)

By Cassie Goff | [email protected]

Accessory dwelling units (ADUs) are legally allowed within single-family residential neighborhoods throughout Utah as of Oct. 1. ADUs used to be regulated by individual municipalities, so cities previously not allowing ADUs, or heavily regulating or restricting them, have been working to update their ordinances and policies. 

(ADUs are permanent residential dwelling units meant for one additional single family within a primary dwelling unit; within the footprint of the primary dwelling unit at the time the internal ADU is created; and for the purpose of offering a long-term rental of 30 consecutive days or longer.) 

On May 5, the Utah State Legislature passed H.B. 82 (Single-Family Housing Modifications) requiring municipalities and counties to classify certain ADUs as permittable. Municipalities and counties are now prohibited from establishing restrictions for ADUs, with limited exception. In addition, the bill sets guidelines for punishing any individual who lists or offers a certain licensed or permitted ADU as a short-term rental. 

As many cities had previously implemented various ordinances and codes related to ADUs within their boundaries, the passing of H.B. 82 was read as an attempt to take control away from local governments. 

“The statewide bill prohibits and limits local authority,” said Cottonwood Heights Community and Economic Development Director Mike Johnson on July 6.

This directly applies to internal ADUs, as the legislature has not yet regulated external ADUs. Meaning, detached garages with apartments above, other detached structures, and tiny homes can still be regulated by local municipalities.

Even though the state legislature allowed municipalities to restrict ADUs through a handful of specific regulations, H.B. 82 stated municipalities were not allowed to further impose or restrict ADUs within their single-family residential zones. 

Municipalities can, however, choose to require building permits or licenses for ADUs. They can require owner-occupancy and one additional off-street parking space. ADUs can be prohibited in a zoning district covering 25% or less of the city’s residential zones and in mobile homes. The use of separate utility meters can be prohibited as well. In addition, municipalities can prohibit short-term rentals in ADUs and hold a record notice of ADU against the property’s title if found in violation. 

Cottonwood Heights was one of the municipalities needing to revisit and revise their Code of Ordinances to ensure compliance on Oct. 1. In 2018 and 2019, the (previous) city council spent months debating various restrictions and regulations for ADUs within the city. Some of those concerns were revisited. 

On-street parking was one of Mayor Mike Peterson’s main concerns related to ADUs in years prior, and still is.  In revising the city’s ADU ordinance, Cottonwood Heights will be requiring one additional (non-tandem) parking stall per ADU. Owner-occupancy will also be required, which can be proven with an affidavit. 

“We are planning to require licensing and inspection,” Johnson said on Sept. 7, ensuring city councilmembers that ADUs within the city will be meeting building code requirements. Cottonwood Heights will also be checking for separate utility meters. 

Requirements for detached ADUs with the city will remain the same, with strict setbacks, parking stall requirements, annual renewal of licensing, and license renewal under new ownership. 

While many of the restrictions set by the state legislature caused varying frustration for councilmembers, one mandate in particular caused concern for many Cottonwood Heights residents. Single-family residential neighborhoods, where ADUs are now legally allowed, includes HOAs (homeowner associations).  

In fact, H.B. 82 makes it illegal for private HOAs and developments with CC&Rs (Covenants, Conditions and Restrictions) to prohibit ADUs. This may directly impact at least 12 neighborhoods within Cottonwood Heights with HOAs. 

“This is the legislature undercutting contracts that have already been made. It will lead to some litigation,” said City Attorney Shane Topham on July 6. 

On Sept. 21, the Cottonwood Heights City Council unanimously voted to enact Chapter 19.75 (Accessory Dwelling Units) within the city code “which authorizes as a permitted use accessory dwelling units contained in the interior of residences in any of the city’s single-family residential zones, as required by H.B. 82 enacted by the Utah Legislature earlier this year.” Ordinance 368 was moved by Councilmember Scott Bracken and seconded by Councilmember Doug Peterson. 

For more information, check out the Accessory Dwelling Units page on the city’s website by visiting and hovering over the “City Services” tab, finding the “Community Development” section, and navigating to the bottom list item of “Accessory Dwelling Units.”