Walla Walla County, WA Accessory Structures: Shed & Carport Rules (2026)

The county's standard side and rear yard setbacks run from five to fifty feet depending on the zoning district under WWCC § 17.18.020, but development condition 7 carves out a specific reduction for accessory buildings. A side and/or rear yard setback may shrink to five feet for a detached garage or similarly sized accessory building once the community development director makes two findings: first, that the structure sits entirely within the rear one-third of the lot, and second, that it will not be unduly detrimental to adjacent and surrounding property or to the zone in which the reduction is requested.

That determination is discretionary and made case by case at building permit review under WWCC Title 14; it is not an automatic right that a property owner can claim simply by building a garage in back. The reduction applies on top of the district's base setback figures in the same table, which otherwise run five to ten feet in most residential and rural zones and up to fifty feet for buildings that house domestic animals or produce offensive noise, dust or odor under development condition 2.

A shed or garage built without securing that determination, or built closer than five feet even after the reduction, is treated the same as any other setback violation under the zoning code: the accessory structure must still be sited to keep required fire separation and drainage clearances, and any placement issue surfaces at building permit review before the county will issue a certificate of occupancy for the structure or the main dwelling.