My last blog was about City of Seattle housing code violations for rental property. Here is how the city defines an Illegal Dwelling Unit:
Summary: The Department of Planning and Development (DPD) Director’s Rule 7-83, “Determining the Existence of a Dwelling Unit for the Purpose of Code Enforcement,” sets out a variety of important factors for determining whether a dwelling unit exists. DPD has found that three critical elements tend to identify a dwelling unit: a kitchen or other food preparation area; bathroom facilities that include both a toilet and a shower or bathtub; and a living area set apart or separated from other living areas by doors, walls, stairways, hallways or common areas.
So be advised, if you are renting by the room, but one of the units contains these three critical elements, then the City would likely consider your house to be a duplex or an ADU. Keep this in mind for the future, if you are a Seattle landlord or property manager.