Office of the Mayor
City of Seattle
Jenny A. Durkan, Mayor
Executive Order 2019-04: Actions to encourage more affordable accessory dwelling units
throughout Seattle
An Executive Order directing the Seattle Department of Construction and Inspections, the Office
of Planning and Community Development, the Office of Housing, and other City departments to
partner with community members and design and construction businesses to develop and
implement strategies to encourage more accessory dwelling units as affordable long-term
housing choices throughout Seattle’s single-family neighborhoods and to study how accessory
dwelling units are addressing our housing affordability crisis and impacting our communities.
WHEREAS, Seattle faces acute housing and livability challenges, including a lack of affordable
housing that constrains where individuals and families can find a home that meets their needs
and make it difficult for longtime residents to age in place; and
WHEREAS, the availability and affordability of housing remains one of the foremost challenges
to our vision of being a vibrant and diverse city where all people can flourish, its effects are
particularly burdensome for low-income people who increasingly struggle to afford any housing
at all and the middle class families that want to make or keep Seattle as their home; and
WHEREAS, the median price for a detached house in 2018 was nearly $800,000, a price far out
of reach for most Seattle areas households. At nearly $2,200 per month, affording even the
median rent for a two-bedroom single-family home exceeds the income of most households,
according to the most recent data on single-family rentals in Seattle; and
WHEREAS, our housing landscape reflects not only market forces and conditions but also many
decades of public- and private-sector exclusion and discrimination, including redlining and
racially restrictive covenants, that limited access to housing ownership and opportunity for
Indigenous communities, people of color, and low-income households, among others; and
WHEREAS, Executive Order 2017-13 affirmed the City of Seattle’s commitment to the Race and
Social Justice Initiative and continued use of a racial equity lens on actions relating to
affordability; and

Office of the Mayor   600 Fourth Avenue, P.O. Box 94749, Seattle, WA 98124   206-684-4000   seattle.gov/mayor

 Executive Order 2019-04 (Actions to encourage more affordable accessory dwelling units throughout Seattle)
July 9, 2019
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WHEREAS, Seattle’s commitment to race and social justice drives our work to make all parts of
Seattle affordable for people of color and low-income people; and
WHEREAS, accessory dwelling units (ADUs) are secondary units within, attached to, or in the
rear yard of a single-family home that create new housing options in areas of our city where
housing is generally unaffordable to most people; and
WHEREAS, Seattle has allowed attached and detached ADUs since 1994 and 2010, respectively,
but less than two percent of single-family lots have added an ADU, creating an opportunity for
new, contextual, space-efficient housing on tens of thousands of lots in our neighborhoods; and
WHEREAS, various hurdles frequently stymie Seattle homeowners who seek to create ADUs,
including but not limited to regulatory barriers, high construction costs, a lengthy and complex
permitting process, and insufficient financing tools; and
WHEREAS, a wide range of households, particularly older adults looking to downsize, seniors
with fixed incomes, low-income households, homeowners with disabilities or other needs, and
multigenerational families could benefit from the flexibility, stability, or supplemental income
that an ADU provides to meet their evolving household needs; and
WHEREAS, ADUs are relatively more affordable to rent than most single-family houses but
remain out of reach for many low-income households; and
WHEREAS, in 2014 the City Council adopted Resolution 31547, directing planning staff to
explore incentives, marketing and promotion strategies, and regulatory changes that could
increase ADU production; and
WHEREAS, Executive Order 2019-02 recognized the need to create affordable, inclusive
neighborhoods and directed City departments to develop and implement strategies to further
affordability and mitigate residential displacement; and
WHEREAS, in May 2018, in order to accelerate the building of more housing units in Seattle, I
issued a directive to Seattle Department of Construction and Inspections (SDCI) to fast-track
pre-approved designs for Detached Accessory Dwelling Units (DADUs) by hiring architects to
develop several standard architectural plans for backyard cottages that could be built and
permitted more quickly and at a lower cost to residents; and
WHEREAS, while efforts to encourage ADU production may have a positive impact on
affordability and displacement overall, other actions beyond regulatory changes are necessary
to ensure ADU policies more equitably benefit lower-income households and households of
color; and

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WHEREAS, other jurisdictions in the Pacific Northwest and elsewhere in North America have
explored various strategies for delivering ADUs that a broader range of households can afford
to own or rent that could serve as a model for Seattle;
NOW THEREFORE, I, JENNY A. DURKAN, Mayor of Seattle, hereby affirm the City’s commitment
to encourage more affordable accessory dwelling units throughout Seattle. To this end, I direct
the following:
Section 1. Assist homeowners in the ADU design and permitting processes.
A. Seattle Department of Construction and Inspections (SDCI) will streamline the design
and permitting process for detached accessory dwelling units (DADUs) by making preapproved plans available at low- or no-cost to homeowners. This work shall:
a. Encourage relatively simple, small, and low-cost DADU designs through an open
call for submissions from the design and construction community, with an
emphasis on encouraging participation by smaller firms, young and emerging
designers, and women- and minority-owned businesses.
b. Engage the public in developing design guidelines for the City to encourage in
DADU plans.
c. Support ongoing innovation in prefab, modular, and other new construction
methods that may reduce construction costs.
d. Issue an ADU construction permit within 30 days for homeowners using a preapproved DADU plan.
e. Implement appropriate actions to ensure DADUs using pre-approved plans
provide long-term housing affordability.
B. SDCI will hire an “ADU navigator” on the permitting staff to help homeowners navigate
the permitting process for ADUs.
C. SDCI will work with the Office of Planning and Community Development (OPCD), Seattle
Information Technology Department (Seattle IT), and other departments to:
a. Develop a one-stop ADU website that provides a comprehensive inventory of
ADU information, guidance, resources; summarizes ADU regulations and
permitting steps; and facilitates connections among prospective ADU owners
and residents and the design and construction community.
i. The website will include a “Can I build an ADU?” service to help
homeowners identify and appraise their ADU options by prototyping an
ADU feasibility tool through the City’s participation in the UW Data
Science for Social Good program.
ii. The effectiveness of this tool shall be reviewed within a year of
implementation to ensure it provides meaningful assistance to
homeowners, designers, and builders.
b. SDCI, along with the Office of Planning and Community Development (OPCD) will
establish and convene an ADU working group, including experienced ADU
designers, builders, owners, landscape architects or arborists, environmental

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advocates and residents to provide educational opportunities—such as tours and
events—to homeowners interested in learning about ADUs and to advise on City
ADU-related programs and resources. This group will also make
recommendations on how to build green ADUs and best preserve trees and
other important environmental features.
Section 2. Pilot strategies for ADUs that support affordability for homeowners and tenants.
A. The Office of Housing (OH) will use the existing Home Repair Program to develop a pilot
program for low-interest financing to help low-income homeowners create ADUs.
B. OPCD, OH, and SDCI will create other innovative strategies and programs to create
affordable ADUs for low-and moderate-income tenants, including:
a. OH, in partnership with OPCD, will explore options for a financing program to
deliver ADUs affordable to low- and middle-income households. The program
should encourage equitable access to the program by exploring loan terms that
are achievable for lower-income homeowners.
b. The City will work with state leaders to create tools and incentives at the state
level to expand availability of affordable housing units supporting a variety of
income levels and innovative housing options to come online more quickly than
standard housing development has in the past.
C. SDCI, in consultation with OPCD and DON and other City entities, will partner with
nonprofits, public agencies, and private organizations on models of affordable ADU
construction, using best practices gleaned from other jurisdictions.
Section 3. Monitor ADU development to measure the development benefits and impacts of
ADU production.
A. By December 1, 2019, Department of Neighborhoods (DON), OPCD, and other City
entities, with the assistance of economists and other stakeholders, will create a baseline
assessment of:
a. The current number, location, and uses of ADUs (e.g. long-term rental, shortterm rental, or other uses);
b. The rental rates of ADUs;
c. The parking usage for ADU residents and the availability of on-site and off-site
parking; and
d. An assessment of green space and tree canopy in the geographic regions of the
City: Northwest, Northeast, Central, Southeast, and Southwest.
B. On December 1, 2020 and every December 1 for each year thereafter, SDCI and OPCD
shall report on the state of each factor listed in section 3 (a) above, together with:
a. The number of ADUs permitted, but not yet constructed.
b. The number of ADUs constructed since the last report, and of those:
c. The number of ADUs:
i. Being used as long-term affordable housing
ii. Being used for short-term rentals
iii. Being used for other purposes
d. The usage rates of the City’s pre-approved plans and financing assistance.

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e. The impacts of ADU construction on green space and tree canopy.
f. An economic assessment of the impact of ADU’s on the availability of and need
for affordable housing.
g. Given the assessment, provide recommendation on how to improve the ADU
program.
h. The impacts that additional ADUs have, if any, on the need for additional transit,
bike infrastructure, and pedestrian amenities and improvements, as well as
other transportation issues (such as traffic congestion).
i. The impact that additional ADUs have, if any, on the need for additional green
space, infrastructure, parks, schools, or other City needs.
Any questions about this Executive Order should be directed to Policy Director Edie Gillis.
Dated this 9th day of July, 2019

Jenny A. Durkan
Mayor of Seattle