Boise City Council approves large zoning-code cleanup and allows tiny homes on wheels with conditions

The Boise City Council on a 4-0 vote approved ZOA/COA 25-3, a city-initiated zoning ordinance amendment that implements 140-plus “continuous improvement” edits to the city’s new zoning code and adds tiny homes on wheels as a permitted accessory dwelling-type in many residential zones.

The amendment package, presented by city planning staff, updates code terminology and structure, refines dimensional and design standards, clarifies process procedures and use tables, and — by council direction — allows tiny homes on wheels as accessory dwellings where ADUs are permitted. The council accepted staff’s recommended edits but excluded proposed changes to the airport influence overlay and one small-multifamily figure for further review.

City planner Diana Dupuy and colleague Andrea Tuning told the council the continuous-improvement approach is an iterative fix to questions and application issues that emerged after the city adopted a new zoning code effective Dec. 1, 2023. Dupuy said staff compiled the changes from thousands of customer interactions, nearly 1,000 applications and 61 public hearings in the code’s first year.

“We permit 1 per site. Each of them will be less than 400 square feet. They’ll need permanent utility connections and will be, subject to the base zone dimensional standards,” Dupuy said of the proposed tiny-home-on-wheels rules. The amendment as adopted allows one tiny home on wheels per lot as an accessory dwelling; the council directed staff to evaluate allowing two on future rounds of edits.

Why it matters: Council members said the package fixes inconsistencies and makes the new code more usable for residents, applicants and departments. Tiny homes on wheels, council members and presenters said, offer a lower-cost housing option and additional flexibility for homeowners and future occupants; several residents and tiny-home participants traveled to testify in favor of formalizing the pilot into zoning rules.

Key details and council direction - Scope: The amendment includes editorial and substantive edits across definitions, allowed uses, use-specific standards, design and development standards, subdivisions, access/connectivity, landscaping and process procedures. Staff called it the first continuous-improvement package following the code’s first year of implementation. - Tiny homes on wheels: Allowed as accessory dwellings in zones where ADUs are permitted; staff recommended treating them like ADUs (one per lot) and required permanent utility hookups and construction with compliant materials. The council directed staff to evaluate permitting two tiny homes on wheels per lot in a future continuous-improvement round and to draft definitions for junior ADUs. - Public input and pilot: City staff noted a 2021 human-centered design effort and a LEAP Housing pilot of six sites informed the recommendations. The Planning and Zoning Commission recommended approval and suggested expanding zones; staff added tiny homes-on-wheels allowance in several mixed-use zones in response. - Exclusions and follow-up work: Council removed proposed redlines to the airport influence overlay (section 11273.d) and struck small-multifamily provision 1103032.G.7 and figure 3.3 for later consideration. Council also directed staff to seek consistent wording where the code currently uses differing standards for effects on neighboring properties and to return with options on ADU/tiny-home counts.

Council concerns and technical points Council members pressed staff on specific language and implementation details: time frames for revised findings after hearings, consistency between phrases such as “will not adversely affect other property in the vicinity” and “will not create a material negative impact on surrounding properties,” how balconies and decking are measured relative to ADU footprint limits, the definition and counting of animal units, and how small-multifamily front-door orientation rules could affect common small-multifamily designs. Staff said many edits came from interdepartmental review (public works, fire, solid waste, code compliance) and from agency comments (including airport and Idaho Housing and Finance-related changes to child-care licensing references).

Public testimony Several participants with direct experience in the LEAP Housing tiny-home pilot urged approval. Owner-builder Jason Bosley said the tiny-home option provides ownership and flexibility for property owners and occupants: “But I just really wanted to speak in favor of the allowing tiny homes on wheels mostly from a flexibility standpoint.” Macy Miller, who helped develop tiny-house policy and who said she has lived in a tiny house for 13 years, praised staff and urged adoption. Armin Toure, an occupant of a tiny house who works in health care, described the program’s community benefits.

Vote and immediate outcome The motion to approve ZOA/COA 25-3 as amended was moved by Council President Nash; the council voted 4-0 in favor (Council members Morales, Nash, Stead and Corliss voting yes; two members absent). The ordinance amendments will be incorporated as directed and staff will return with additional edits in the next continuous-improvement cycle planned for 2026.

What’s next Staff said they will launch a zoning-code website and a planned fall engagement to prepare for the 2026 continuous-improvement cycle. The council also directed staff to evaluate the ADU/tiny-home-per-lot question and to standardize language addressing impacts on neighboring properties.