Accessory buildings include detached garages, sheds, greenhouses, barns, and other buildings that are "customarily subordinate or incidental to and located on the same lot with a principal use, building or structure." (AMC 21.35.020.B)
Accessory buildings are regulated by AMC 21.45.030:
A. No accessory building shall be erected or maintained in any required yard, except that:
- buildings accessory to a residential use may be erected in a required rear yard which is adjacent to an alley; and
- sheds of 150 square feet or less and not attached to a foundation may be erected in a required side or rear yard.
- dog runs and dog houses not attached to a foundation may be erected in a required side or rear yard.
B. No separate accessory building shall be erected closer than ten feet to any principal structure on the lot or an abutting lot or tract.