ADU's (Accessory Dwelling Units)

ADU

If you are interested in adding an ADU (Accessory Dwelling Unit) to your property you will need a permit.  These structures are also known as tiny homes, granny flats, in-law units, mother-in-law apartments, or any other structure that has a kitchen, living space and bathroom separate from the main house.  

 

Step-by-Step Process

 

1. Get land use approval through the Planning Division.  Once approval is obtained move on to step 2 . Follow the link for the ADU Land Use Application

 

2. Submit for engineering permits for any work in the public right-of-way.

 

3. Submit for building permits online for building, plumbing, mechanical and electrical (Washington County). 

 

Fee Information

 

To avoid any surprises, plan your budget in advance including all fees.  ADU's typically incur system development charges (SDC's) in addition to permit fees for accessory, plumbing or mechanical work.  The fees for an ADU can be 15-25% of your overall budget.  Get a good idea of your fees using the links below:

 

SDC Fees:

Parks Residential SDC

School District CET

Transportation Development Tax (Residential Condominium/Townhouse rate)

 

Permit Fees:

Building Permit Fees

Mechanical Permit Fees

Plumbing Permit Fees

 

 

If you have building questions, please contact the Building Division at 503-691-3044.