Ordinance No. 2025-26 ADU Code Updates (Approved 101425)Page 1 of 5
ORDINANCE NO. 2025-26
AN ORDINANCE of the City of Bainbridge Island,
Washington, relating to Accessory Dwelling Units
amending Bainbridge Island Municipal Code Sections
2.16.060, 2.16.120, and 18.09.030, establishing an effective
date and providing severability
WHEREAS, the City of Bainbridge Island is a member jurisdiction to the Kitsap
Regional Coordinating Council (“KRCC”); and
WHEREAS, the KRCC Land Use Technical Advisory Council created a project
to develop and implement a program to distribute building plans for Accessory Dwelling
Units (ADUs) that were pre-approved by licensed architects and structural engineers; and
WHEREAS, planning and development standards for ADUS are contained in
Section 18.09.030 in the Bainbridge Island Municipal Code (BIMC); and
WHEREAS, certain code provisions in BIMC Section 18.09.030.I.5 prevent the
smooth and straightforward use of the pre-approved ADU plan sets; and
WHEREAS, on July 22, 2025, at a regular business meeting, the Bainbridge
Island City Council after a staff presentation on pre-approved ADUs and barriers in code
preventing their smooth and straightforward use, gave direction to develop an ordinance
to address barriers in code for the preapproved ADU plan sets; and
WHEREAS, on August 14, 2025, the Planning Commission considered
Ordinance No. 2025-26 to amend BIMC Section 18.09.030.I.5; and
WHEREAS, on September 11, 2025, the Planning Commission held a public
hearing on the draft amendments and recommended approval to the City Council; and
WHEREAS, the City Council reviewed the Planning Commission’s
recommendation at a regular business meeting on October 14, 2025; and
NOW, THEREFORE, THE CITY COUNCIL OF THE CITY OF
BAINBRIDGE ISLAND, WASHINGTON, DOES ORDAIN AS FOLLOWS:
Section 1. Section 2.16.060 of the Bainbridge Island Municipal Code is hereby
amended to read as follows:
2.16.060.B. Applicability.
1. A variance is authorized only for lot coverage, size of structure, or size of
setbacks. Variances are not authorized for changes in density requirements,
building or structure height requirements, open space requirements, or
expanding a use otherwise prohibited.
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2. The minor variance process may be used for minor deviations from zoning
standards in BIMC Title 18 as determined by the director. Minor projects should
be limited to: (a) projects that are exempt from review under the State
Environmental Policy Act (SEPA), or (b) proposals for less than a 25 percent
encroachment in required yards, (c) proposals for less than a 25 percent increase
in lot coverage, or (d) proposals related to single-family residences on an
existing lot. All other variances shall be processed using the procedures set forth
in BIMC 2.16.120.
3. This process may also be used for minor variation(s) from the engineering
requirements of the adopted city of Bainbridge Island engineering and
development standards if the requested variation will further the purposes of the
BIMC and is approved by the department director, after recommendation by the
city engineer and/or the fire marshal.
4. For projects participating in a housing design demonstration project pursuant to
BIMC 2.16.020.S, design guidelines may be varied if the applicant can
demonstrate that deviation from the guidelines will facilitate meeting goals of
the housing design demonstration program.
5. This procedure is not available to obtain variances from subdivision standards in
BIMC Title 17 or to obtain variances from BIMC Title 18 zoning standards
cross-referenced in BIMC Title 17 as part of a short subdivision, long
subdivision, or large lot subdivision approval or amendment process, except for
those engineering standards covered by subsection B.3 of this section.
6.This procedure is not available to allow the siting for an For one-story accessory
dwelling units, an applicant may apply for up to a fifty-percent setback
reduction; no other variances are available where it would not otherwise be
permitted.
7.A variance shall not be granted solely because of the presence of nonconformities
in the vicinity of the subject site.
8. The provisions of this section shall supplement those of
BIMC 2.16.020 and 2.16.030. In the event of a conflict between the provisions of
BIMC 2.16.020 or 2.16.030 and this section, the provisions of this section shall
govern.
Section 2. Section 2.16.120 of the Bainbridge Island Municipal Code is hereby
amended to read as follows:
2.16.0120.B. Applicability.
1. The major variance process may be used for deviations from zoning standards in
BIMC Title 18 that the director determines exceed the threshold for minor
variances under BIMC 2.16.060. A variance is authorized only for lot coverage,
size of structure or size of setbacks. Variances are not authorized for changes in
density requirements, building or structure height requirements, open space
requirements, or expanding a use otherwise prohibited.
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2. This procedure is not available to obtain variances from subdivision standards in
BIMC Title 17 or to obtain variances from BIMC Title 18 zoning standards
cross-referenced in BIMC Title 17 as part of a short subdivision, long
subdivision, or large lot subdivision approval or amendment process.
3.This procedure is not available to allow the siting for an For one-story
accessory dwelling units, an applicant may apply for up to a fifty-percent
setback reduction; no other variances are available where it would not otherwise
be permitted.
4.A variance shall not be granted solely because of the presence of
nonconformities in the vicinity of the subject site.
5. Variances from the city’s noise regulations in Chapter 16.16 BIMC are available
through the noise variance process in Chapter 16.16 BIMC and are not available
through the major variance process in this section.
6. The provisions of this section supplement those of
BIMC 2.16.020 and 2.16.100 when the application is for a major variance. In the
event of a conflict between the provisions of BIMC 2.16.020 or 2.16.100 and this
section, the provisions of this section shall govern.
Section 3. Section 18.09.030 of the Bainbridge Island Municipal Code is
hereby amended to read as follows:
18.09.030.I.5. Accessory Dwelling Unit.
a.An accessory dwelling unit (ADU) may be created within, or detached from,
any single-family dwelling, whether existing or new, as a subordinate use,
where permitted (“P”) by this chapter.
b. In the shoreline jurisdiction, an accessory dwelling unit may be created within,
or detached from, any single-family dwelling, whether existing or new, as a
subordinate use, where conditional (“C”) pursuant to this chapter. See Chapter
16.12 BIMC for shoreline conditional use process.
c.Only one accessory dwelling unit may be created per parcel.
d.No A variances shall be granted application is only available for up to a fifty-
percent setback reduction for one-story an accessory dwelling units.
e.One off-street parking space shall be provided in addition to off-street parking
that is required for the primary dwelling.
f.Accessory dwelling units shall be designed to maintain the appearance of the
primary dwelling as a single-family dwelling, containing 1,000 900 square feet
of floor area or less. However, if the accessory dwelling unit will be located
within a building existing as of the approval date of Ordinance No. 2015-16
(for example, in a basement) the city may allow an increased size in order to
efficiently use all floor area. If a separate outside entrance is necessary for an
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accessory dwelling unit located within the primary dwelling, that entrance must
be located either on the rear or side of the building.
g. If an accessory dwelling unit is constructed in conjunction with a garage, the
square footage of the garage shall not count towards the 1,000 900-square-foot
limitation.
h. An accessory dwelling unit not attached to the single-family dwelling may not
contain any accessory use other than a garage.
i.No recreational vehicle shall be an accessory dwelling unit.
j. When stairs utilized for the ADU are enclosed within the exterior vertical walls
of the building, they shall not count towards the floor area of the ADU.
k.The ADU shall should share a single driveway with the primary dwelling.
l.School impact fees and qualified exemptions from those fees as provided in
Chapter 15.28 BIMC shall apply.
m.All other applicable standards including, but not limited to, lot coverage,
setbacks, parking requirements, and health district or city requirements for
water, sewer, and/or septic must be met.
n. In the Mixed Use Town Center, new accessory dwelling units are only
permitted as part of a housing design demonstration project single-family
subdivision approved pursuant to BIMC 2.16.020.S.
Section 2. Severability. Should any section, paragraph, sentence, clause, or
phrase of this ordinance, or its application to any person or circumstance, be declared
unconstitutional or otherwise invalid for any reason, or should any portion of this
ordinance be preempted by state or federal law or regulation, such decision or
preemption shall not affect the validity of the remaining portions of this ordinance or
its application to other persons or circumstances.
Section 3. This ordinance shall take effect and be in force five (5) days from
its passage and publication as required by law.
PASSED by the City Council this 14th day of October, 2025.
APPROVED by the Mayor this 14th day of October, 2025.
Ashley Mathews, Mayor
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ATTEST/AUTHENTICATE:
Christine Brown, MMC, City Clerk
FILED WITH THE CITY CLERK:
PASSED BY THE CITY COUNCIL:
PUBLISHED:
EFFECTIVE DATE:
ORDINANCE NUMBER:
October 10, 2025
October 14, 2025
October 19, 2025
October 23, 2025
2025-26