River Heights planning commission refines ADU draft, sets 90‑day rental minimum and sends revisions for legal review

Keenan Ryan, Chair of the River Heights Planning and Zoning Commission, led a detailed review of a proposed accessory dwelling unit (ADU) ordinance on April 14, asking staff to combine competing drafts and return a single, cleaned‑up version for legal and technical review. Commissioners resolved several open items after discussion that drew examples from state language and nearby cities’ ordinances.

The commission agreed to standardize terminology by striking the word "external" and using "detached" for ADUs sited separately from a primary dwelling, while keeping "internal" for ADUs within a house. Commissioners favored aligning definitions with state practice and said the revised draft should be the working base document.

On occupancy and size limits, the commission endorsed a conservative approach used in nearby ordinances: caps tied to bedrooms (2 persons per bedroom) and a practical overall size limit for ADUs. Commissioners repeatedly cited the common 1,200‑square‑foot cap used by neighboring jurisdictions for detached ADUs and agreed unusual cases could be handled conditionally.

Parking and inspections were clarified. The working draft removes a state‑minimum parking exception and points to the city’s chapter‑10 parking standard—effectively keeping a two off‑street parking‑space requirement for ADUs. Commissioners also agreed inspections, certificates of occupancy and building permits are handled by Cache County; the ADU draft will require compliance with Cache County building rules rather than duplicating inspection procedures in the city code.

The commission discussed utilities and septic systems. The draft will state that an owner is billed for each dwelling on a lot (charges combined on a single bill) and that residential units served by an existing septic system must obtain Cache County Health Department approval for additional ADU use. Commissioners asked staff to clarify billing language to reflect one bill with separate charges where applicable.

The group debated whether the ADU definition should require a "separate kitchen." After discussing studio‑style living spaces and the needs of small households, commissioners removed the phrase "separate kitchen" and kept a requirement that ADUs provide provisions for living, sleeping, cooking and sanitation on a year‑round basis.

To limit short‑term commercial use, the commission voted to set a minimum rental term for ADUs at 90 consecutive days. Commissioners said that restriction better protects the intent of ADUs as housing stock rather than short‑term vacation rentals.

On placement and dimensional rules, the commission directed the draft to: prevent ADUs in utility easements (minimum 5‑foot offset), clarify side/rear/corner lot setbacks (typical 5‑foot side/rear with certain corner/adjacency conditions at 10 feet), and tie ADU height to the primary dwelling (do not exceed the primary dwelling’s height). The draft will avoid an isolated 15‑foot maximum and instead reference the primary‑building height rule and applicable table of zone setbacks and heights to prevent conflicts.

Next steps: the commission asked Recorder Sheila Lind to incorporate the agreed changes, circulate the revised draft to commissioners, and then send the draft to the city attorney and city engineer for technical review; a public hearing will be scheduled after those reviews are returned.

What this means locally: if adopted following revisions and review, the changes will standardize ADU terminology, limit ADU sizes in line with neighboring cities, require clear utility/septic approvals, maintain two‑space parking for ADUs, and require ADU rentals to be for at least 90 consecutive days. The commission did not adopt the ordinance at the meeting; it directed staff to finalize the draft and seek attorney/engineer feedback before formal public hearing and adoption.