Our new project in Ballard has just begun, and we’re already running into a multitude of problems.  One of the first major setbacks in our project is three illegal dwelling units.  Many of our clients have also run into similar issues with their investments, and we’re going to take a minute and discuss some of the ways to navigate and deal with this issue in the city of Seattle.

According to the city, an illegal dwelling unit is a living space that was created without a permit.  The City defines a living space as having one or more of the following:

  • Kitchen or other food preparation area
  • Bathroom
  • A living area separated from other living areas (by a door, wall, stairway, hallway, etc)


Seattle’s Land Use Code does not allow single-family homes to have accessory dwelling units (ADU) without the proper permit, however, they can be added as long as there is a permit.  Our current project is a four-unit home with one attic space, the main floor living area, and then two additional basement units.  None of the units have been permitted and all have bathrooms, kitchens, and locked doors or walls to separate from the other units – fitting the illegal criteria as set by the City.

Illegal attic dwelling unit 
Illegal basement dwelling #1




There are two ways to move forward as an investor, you can get the proper permits for the units, and then fix it up as a multiple unit home. However, we want to restore this house to its original style, which means returning it to a legally permitted single-family home.  Additionally, the house was built with incredible basement potential for an ADU; something that buyers in the Seattle area are looking for in a home.  In order to keep one of the basement units, we now have to obtain the proper permits remove the illegal units, and remodel and legalize the main basement ADU.


The process of legalizing an illegally built unit is fairly simple, remove it.  The City of Seattle has outlined a protocol for removing illegal units starting with obtaining the correct demolition permits. You can apply for a permit online here.   After the proper permit has been obtained, in order to legally remove the unit, the food preparation area must be removed as well as all physical barriers and locks that separate the units within the house.  However, the City of Seattle understands the unique qualities of each property, and requirements to legalize the home can vary depending on the scope of work.

In addition to removing illegal units, we also need to legalize one of the basement units.  If we do not legalize the unit, we could face fines from the city.  As a unit that was illegally established, the City of Seattle defines the space as a “Nonconforming Use.”  Moving forward, in order to establish the basement as a legal ADU there are a series of requirements that must be met and vary depending on the property. In regards to Jones Avenue, we need to comply with all codes listed below:

  • The property owner must occupy the home as a permanent or main residence.
  • The owners must sign, notarize and record with King County.
  • The total number of residents cannot exceed eight unless all residents are related.
  • The unit must have a separate, locking entrance.
  • The ADU is within an existing building.

Do you have an investment property with illegal dwelling units? Contact Us and our experts will help you navigate the permit process to get your project on track.

Our next step in our Jones Avenue is asbestos testing.  Stay tuned for our next Jones Avenue update as we take you through the steps of abating a home!