Accessory Structures in Yakima, WA (2026)
5 verified accessory structures rules for Yakima, Washington, sourced directly from the municipal code and official government pages.
Verified from official government sources
ADU Rules
Yakima YMC 15.09.045 governs Accessory Dwelling Units (ADUs) — attached, garage-mounted, or detached stand-alone — with a 1,000 sq ft maximum floor area, exterior design that matches the primary dwelling, and one ADU per single-family lot. Washington HB 1337 (2023, RCW 36.70A.680-696) now requires Yakima as a GMA-planning city to allow at least two ADUs per single-family lot, eliminate owner-occupancy requirements, and waive off-street parking minimums within 0.5 mile of major transit. Yakima must update YMC 15.09.045 to comply by mid-2025 (six months after its next periodic GMA comprehensive plan update).
Yakima Accessory Dwelling Units (YMC 15.09.045 + WA HB 1337)
Few RestrictionsShed Rules
Yakima YMC 15.05 Table 5-1 places detached residential accessory structures (sheds, detached garages, carports) at typically 5 ft minimum side and rear setbacks in SR, R-1, R-2, and R-3 zones, with no front-yard setback closer than the principal building. The 2018 Washington State Building Code (RCW 19.27) — based on 2018 IBC/IRC — exempts one-story detached residential accessory structures up to 200 sq ft from a building permit, provided no electrical, plumbing, or mechanical systems are added. Sheds over 200 sq ft, or any shed with utilities, require a Yakima Code Administration building permit.
Yakima Shed Rules (YMC 15.05 + WSBC)
Few RestrictionsGarage Conversions
Converting a Yakima garage to habitable space requires a building permit and electrical permit from the Yakima Code Administration Division under the 2018 Washington State Building Code (RCW 19.27). A garage-to-ADU conversion that adds a kitchen and separate entrance falls under YMC 15.09.045 ADU rules — 1,000 sq ft max floor area (HB 1337 may raise the cap), matching exterior, and accessory-structure setbacks. Per WA HB 1337 (RCW 36.70A.680), Yakima must allow garage-conversion ADUs without owner-occupancy mandates and without off-street parking replacement within 0.5 mile of major transit.
Yakima Garage Conversion (YMC 15.09 + WSBC)
Some RestrictionsCarport Rules
Yakima YMC 15.05 Table 5-1 sets detached carport setbacks at typically 5 ft minimum side and rear in SR, R-1, R-2, and R-3 zones. Attached carports follow the principal-building setbacks for the zone. Construction requires a building permit from the Yakima Code Administration Division under the 2018 Washington State Building Code (RCW 19.27) with engineered anchorage for Yakima Valley wind loads (~90-100 mph) and Seismic Design Category D1. Enclosing a carport with walls converts it to a garage and requires a new permit with fire-separation, garage door, and vehicle barrier per IRC R302.6.
Yakima Carport Rules (YMC 15.05 + WSBC)
Few RestrictionsTiny Homes
A tiny home on a permanent foundation in Yakima is treated either as a primary single-family dwelling (must meet YMC 15.03 zoning standards for the zone) or as an Accessory Dwelling Unit under YMC 15.09.045 (1,000 sq ft cap, matching exterior, accessory-structure setbacks). The 2018 Washington State Building Code (RCW 19.27 + WAC 51-50) adopts IRC Appendix Q (Tiny Houses) — allowing reduced ceiling heights, ladder access to lofts, and small-stair geometry. Tiny homes on wheels (THOWs) registered as RVs cannot serve as a permanent residence in residential zones. WA HB 1337 (RCW 36.70A.680) requires Yakima to allow ADU-style tiny homes including detached units.
Yakima Tiny Home Rules (YMC 15.09.045 + WSBC)
Some RestrictionsLooking for Yakima County county-wide rules?
County ordinances apply to unincorporated areas and may supplement Yakima city rules.
Accessory Structures in Yakima County →