What is an Accessory Dwelling Unit (ADU)?
Sometimes referred to as mother-in-law unit, granny shack, or backyard cottage, Accessory Dwelling Units (ADUs) are small, independent residential units located on the same lot as a stand-alone single-family home. ADUs provide the same essential functions as a typical single-family residence, complete with a kitchen, sleeping area, and bathroom, but are smaller or "accessory" to the primary residence. For more information, view the Accessory Dwelling Unit Handout.
The Puget Sound region continues to face significant challenges related to housing supply and affordability. State and municipal legislation continue to advance Accessory Dwelling Units (ADUs) as one way to create affordable housing options, diversify existing housing stock, and control sprawl.
To promote ADU development, the City developed a Permit Ready ADU (PRADU) Program that offers residential property owners to select from eight pre-approved, designed, and engineered ADU model base plans. The model base plan range in size from 415 - 1,000 sq. ft. and vary in architectural styles so that property owners can select an ADU that is complementary to the existing single-family dwelling.
City of Renton Permit Ready ADU (PRADU) Program
The city is offering free ADU model base plans for residential property owners within the City's jurisdictional boundary. The model base plans and PRADU Program are designed to simplify the building permit application and review process. Applicants utilizing the City's pre-approved plans will work with staff one-on-one to design their ideal site plan and go through an expedited review process, providing the applicant with significant cost savings that can be applied toward construction.
Interested in applying for a PRADU?
Please email Planning Customer Service for more information or call (425) 430-7294.
After working with our Planning Customer Service, you will be able to submit for a PRADU through the Civic Access Self-Service Portal.
PRADU Architectural Designs
Available models are displayed in the drop-down menus below. The floor plans are online.
More information and the PRADU Lookbook are online.
Looking for a Contractor to build your PRADU?
Property owners/applicants have the right to hire any qualified, licensed professional for the purposes of PRADU construction, but as requested by PRADU applicants, we have compiled a list of contractors with knowledge and interest in the PRADU Program. The companies listed here have self-certified that they are familiar with the City of Renton PRADU Program. The PRADU Program Professional Services Roster is open by request, and the City does not endorse, recommend, or have any involvement in selecting professionals.
PRADU Professional Services Roster (to view the list, click the link and when the page opens click the down arrow next to the printer icon to download the spreadsheet)