Accessory Dwelling Units

Accessory Dwelling Units (ADUs) are becoming increasingly popular as a way for communities to create more workforce rental options, while also providing a means to generate income, add housing flexibility, and age-in-place.

You may know these as backyard cottages, mother-in-laws, or granny flats. Whatever you call them, ADUs are one of the most immediate housing solutions available to us. By utilizing the existing space our backyards or easier yet, perhaps in a garage, basement, or attic, we can create flexible workforce rentals.

Considering an ADU?​

The City and County both allow and encourage ADU development. To learn specific details about design, permitting, and other ADU guidelines review these guides for the City of Port Townsend and Jefferson County
Some key points include:

  • Two ADUs are now allowed throughout the city for single family residences. They can be one structure or separate.  
  • The City caps a detached unit size at 800 square feet and an attached unit at 1000, while the County limits all ADUs to 1250 square feet
  • Both City and County define an ADU as a complete, independent living facility that has its own address and external entrance
  • In the City, an owner can rent out both the primary home and the ADU, but in the County you must reside in one of the units. The city does not allow either to be a short term rental. 
  • In the City, Tiny Homes on Wheels (THOW) are permitted if built and inspected to certain standards. The city has prepared som documents on how to navigate the process.

You can review the municipal codes for complete details:

Additionally, HSN has produced the Permit Navigator informational video series with local builders and designers that walk the viewer through, step by step, the process of completing an ADU building permit (note: these videos were produced in 2021, so some details have changed)

Considering an ADU?​

Here we have compiled a collection of ADU materials including our overview guide the ABC’s and 123’s of ADUs, a cost calculator, and several landlord/tenant materials. Our aim is to make it easy for you to support workforce housing development here at home.

Is there more information you would like to see or have some expertise you would like to share with the community? Let us know! These materials were made possible by volunteers and community activists that support affordable housing. 

Considering an ADU?​

HSN is committed to enabling more affordable housing in Jefferson County. One of the quickest ways we can do that is through utilizing ADUs. 

  • Do you have land where a small, new additional dwelling unit might fit?
  • Do you have a basement, garage or other area where re-modeling might yield a rental unit?
  • Would you like to earn rental income while helping provide more affordable housing?
  • Do you have questions about financing, permitting, or construction that have held you back?
  • Do you want to explore your options now?

If the answer is ‘yes’ to any of these following questions, we’d love to speak with you further.

Fill out the short form  with as much detail as you can and we’ll reach out to start a conversation.

Highlighting a Local ADU Project

Rebecca and Andrew know first hand how difficult it can be for young families to get a foothold in this community. 

Between financing from their primary residence, assistance from the LION Network and putting in some hard work, they now have added one more unit of workforce housing to our community.


Local Advocacy Opportunities

  • ‘Stock Plans’ are housing plans that  have been accepted as well-designed and partially permitted by municipalities. They are great for ADUs or primary residence and both expedite the process for builders and reduce fees for the homeowner. Jefferson County and the City of Port Townsend are both considering adopting stock plans for our community. Would you like to see this happen here? Write us and say why!
These free resources are provided as part of our Share Our Spaces campaign