Accessory Structures in Kennewick, WA (2026)
2 verified accessory structures rules for Kennewick, Washington, sourced directly from the municipal code and official government pages.
Verified from official government sources
ADU Rules
Kennewick allows two accessory dwelling units per lot in every residential zone, each capped at 1,100 square feet and 24 feet in height if detached, under KMC 18.12.020: a local rule that already tracks Washington's 2023 HB 1337 statewide floor.
Kennewick Accessory Dwelling Unit Zoning Rules
Some RestrictionsKennewick Municipal Code § 18.12.020 (Ord. 6037, Sec. 1, 2023; Ord. 5528 Sec. 1, 2013; Ord. 5180 Sec. 1, 2007)
Two accessory dwelling units shall be permitted in all residential zoning districts in the following configurations: (a) One attached accessory dwelling unit and one detached accessory dwelling unit; (b) Two attached accessory dwelling units; or (c) Two detached accessory dwelling units... The maximum height for an ADU that is detached from the primary unit shall be 24 feet... The total gross f...
Shed & Carport Rules
In Kennewick's R and HMU districts, detached sheds and accessory buildings must sit at least 5 feet from side and rear lot lines, 10 feet from the main house, and no taller than 20 feet.
Kennewick Shed and Accessory Building Setbacks
Some RestrictionsKennewick Municipal Code § 18.27.030 (Ord. 5744 Sec. 1, 2018; Ord. 5715 Sec. 1, 10-17-2017; Ord. 5180 Sec. 1, 2007)
Accessory buildings must comply with applicable setbacks. Except in C, I, PF, UMU, and OS districts, detached accessory buildings may not be over 20 feet high. In all R and HMU districts, no accessory building may be closer than ten feet from any building on the same lot unless the accessory structure is constructed in accord with the International Building Code, in which case the separation ca...
Looking for Benton County county-wide rules?
County ordinances apply to unincorporated areas and may supplement Kennewick city rules.
Accessory Structures in Benton County →