HomeMy WebLinkAboutO-3351 - Accessory Dwelling Unit Interim RegulationsAccessory Dwelling Unit Interim Regulations Page 2 of 11
WHEREAS, significant reorganization of the code is needed to improve readability and
to address the requirements of HB 1337; and
WHEREAS, as it is most efficient to amend the Accessory Dwelling Unit and accessory
structure standards concurrently, and will enhance readability to have these subjects in
separate chapters, the existing Chapter 22C.180, Accessory Structures, is proposed to be
repealed and replaced with two new municipal code chapters: 22C.180, Accessory Structures,
and 22C.185, Accessory Dwelling Units; and
WHEREAS, the City Council wishes to ensure broad public participation in the
development of Accessory Dwelling Unit and accessory structure standards; and
WHEREAS, ensuring broad public participation and drafting amendments to the
municipal code require additional time; and
WHEREAS, City staff have prepared interim regulations pertaining to Accessory
Dwelling Units and accessory structures, for which environmental review occurred and for
which a State Environmental Policy Act (SEPA) Determination of Non-Significance was issued
on June 6, 2025; and
WHEREAS, the State Growth Management Act (RCW 36.70A) requires notice and
broad public participation when adopting or amending the City's comprehensive plan and
development regulations; and
WHEREAS, pursuant to RCWs 35A.63.220 and 36.70A.390, the Marysville City
Council may adopt an interim zoning ordinance that extends for a period of up to six months,
if the Council holds a Public Hearing on the interim zoning ordinance within sixty days after
adoption and subsequently adopts findings of fact to support the interim zoning ordinance;
and
WHEREAS, applicants would be able to submit development applications under the
proposed interim zoning ordinance; and
WHEREAS, during this six-month period, the City Council will consider permanent
Accessory Dwelling Unit regulations; and
WHEREAS, while the interim zoning ordinance is in effect, the City Council will direct
City staff to consider all relevant facts, perform all necessary analyses, and work with the
Planning Commission to prepare permanent Accessory Dwelling Unit regulations; and
WHEREAS, during this six-month period, an ordinance which includes permanent
Accessory Dwelling Unit and accessory structure regulations will be drafted and processed
according to applicable law, which will include a notice of Public Hearing(s), and
consideration/action on the final ordinance by City Council; and
WHEREAS, the City Council considered this interim ordinance during the Council’s
regular meeting on June 23, 2025;
WHEREAS, the City Council will hold a Public Hearing on July 14, 2025 to accept public
testimony and to consider such interim zoning ordinance; and
WHEREAS, the City Council adopts the findings and conclusions outlined in Section 2;
and
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WHEREAS, the interim zoning ordinance is necessary for the public health, safety,
and welfare; and
WHEREAS, this is a public emergency ordinance necessary for the protection of public
health and public safety, and should be effective upon adoption.
NOW, THEREFORE, THE CITY COUNCIL OF THE CITY OF MARYSVILLE,
WASHINGTON, DO ORDAIN AS FOLLOWS:
Section 1. The purpose of this interim zoning ordinance is to allow the City adequate
time to complete the activities described in the recitals, which are incorporated by this
reference. These activities will be performed while an interim zoning ordinance establishing
interim Accessory Dwelling Unit and accessory structure regulations are in effect. The City
Council finds that the adoption of an interim zoning ordinance for a six-month period will best
serve the public interest. Said interim regulations are set forth in attached Exhibits A and
B.
Section 2. The City Council makes the following findings of fact and conclusions in
support of the interim zoning ordinance.
(1) The City Council adopts and incorporates the recitals above as findings.
(2) The interim zoning regulations set forth in Exhibits A and B will allow for accessory
dwelling units that comply with RCW sections 36.70A.680, 681, and 696, while
establishing interim standards promote accessory dwelling units that align with the
community’s vision.
(3) It is in the best interest of City of Marysville to adopt interim accessory dwelling
unit and accessory structure regulations at this time, pending further study and
public engagement on the final development regulations.
(4) The proposed interim zoning regulations will promote the public health, safety,
moral, and general welfare, and are consistent with the goals and policies of the
Comprehensive Plan.
(5) This ordinance satisfies the procedural and substantive requirements of, and is
consistent with, the GMA.
Section 3. The City Clerk is authorized and directed to provide the necessary public
notice and schedule a Public Hearing on this interim zoning ordinance to be held during the
City Council’s regular meeting on July 14, 2025, or within 60 days of the adoption of this
Ordinance, as provided in RCW 35A.63.220 and RCW 36.70A.390. After the Public Hearing,
the City Council may adopt additional legislative findings in support of this Ordinance and/or
otherwise modify the provisions of this Interim Zoning Ordinance.
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Exhibit A
Chapter 22C.180
ACCESSORY STRUCTURES
Sections:
22C.180.010 Purpose.
22C.180.020 Access structure standards.
22C.180.010 Purpose.
The purpose of this chapter is to allow for residential accessory structures to be established
which are incidental to the primary residential use of a single-family residence or Middle
Housing residence, while ensuring compatibility with surrounding residential uses. The
accessory structure must be clearly subordinate to the primary use. Accessory structures or
uses may not be established until the principal structure is constructed on the property.
22C.180.020 Accessory structure standards.
In the zones in which a residential accessory structure is listed as a permitted use, the
community development director or designee shall review all proposals for accessory
structures. The following standards and regulations shall apply to all proposed accessory
structures.
(1)
Table 1
Front setback See MMC 22C.010.080 for standard lots and MMC
22G.080.080 for PRD lots.
Side setback 5 feet
Side street setback 10 feet along non-arterials; 15 feet along arterials
Rear yard setback 1, 2, 3 5 feet (one-story structure); 10 feet (when the entrance
faces the rear yard or for two-story or greater structure
in PRDs); 15 feet (two-story structure or when
accessory structure entrance faces an alley with right-of-
way less than 10 feet wide)4
Building, and Impervious
Coverage
See MMC 22C.010.080 for standard lots or MMC
22G.080.080 for PRD lots
Accessory Structure
Footprint 5
On lots under one-acre, accessory structures not
containing an accessory dwelling unit are further limited
to 80 percent of the footprint of the primary residence. 6
Height 20 feet (lots under one acre)6; or
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30 feet (lots over one acre, or lots under one acre where
the accessory structure contains an accessory dwelling
unit)
1 Accessory structures in Planned Residential Developments are subject to the rear yard
setbacks set forth in MMC 22G.080.080.
2 No more than 50 percent of the required rear setback area (i.e. back 20 feet of the lot)
may be covered with accessory structures.
3 An accessory structure, which is located in the rear setback area, may be attached to
the principal structure; provided, that no portion of the principal structure is located
within the required yard setbacks for principal structures in the zone.
4 The increased alley setback applies to vehicle access points from garages, carports,
fenced parking areas or other accessory structure. Exception: in the Downtown
Neighborhood, the rear setbacks outlined in the table above may be reduced to two feet
from the rear lot line; provided, that the alley right-of-way is a minimum of 20 feet in
width. Where the alley right-of-way is less than 20 feet in width, the property owner shall
be required to dedicate to the city sufficient property to widen the abutting alley to the
full width as measured from the design centerline, to conform to the applicable road
standards specified by the city engineer. Upon dedication of the necessary right-of-way,
the rear setback may be reduced to two feet from the rear lot line. Where an existing,
nonconforming structure located in the Downtown Neighborhood is internally remodeled
to include an accessory dwelling unit, but the footprint of the structure is not increased,
the structure can be allowed to remain at a zero setback; provided, that the right-of-way
is 20 feet in width.
5 The community development director is specifically authorized to allow an increase in
the size of a detached accessory structure over the requirements outlined in this table;
provided, that the accessory structure(s) shall be compatible with the principal structure
and/or neighborhood character. To make this determination, the community development
director may consider such factors that include, but are not limited to, view obstruction,
roof pitch, building materials, screening and landscaping, aesthetic impact on surrounding
properties and streetscape, incompatible scale with dwellings on surrounding properties,
and impact on neighborhood character. The community development director shall also
have the authority to impose greater setback requirements, landscape buffers, or other
locational or design requirements to mitigate the impacts of accessory structures which
are greater in size than otherwise allowed by this section.
6 The community development director may allow minor deviations to the 20-foot height
and the 80 percent building footprint limitations applicable to properties under one acre
as necessary to accommodate industry standards for building dimensions.
(2) A detached garage, carport or other permitted accessory structure may be in the front
or side yard, or on the flanking street side of a corner lot, only if the applicant demonstrates
to the satisfaction of the community development director that:
(a) The accessory structure is consistent with the architectural character of the
residential neighborhood where it will be located, and the principal structure on the
lot; and
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(b) The accessory structure shall have a roof pitch similar to the principal structure
and have siding and roofing materials similar to or compatible with those used on the
principal structure. No metal siding or roofing shall be permitted unless it matches the
siding and roofing of the principal structure, or unless it is a building material that is of
a residential character such as metal tab roofing or other products consistent with
standard residential building materials. Plans for the proposed accessory structure(s)
indicating siding and roofing materials shall be submitted with the application.
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Exhibit B
Chapter 22C.185
ACCESSORY DWELLING UNITS
Sections:
22C.185.010 Purpose.
22C.185.020 Accessory dwelling unit standards.
22C.185.010 Purpose.
The purpose of this chapter is to allow for accessory dwelling units, to be established which
are incidental to the primary residential use of a single-family residence or Middle Housing
residence, while ensuring compatibility with surrounding residential uses. The accessory
dwelling unit(s) must be clearly subordinate to the primary use. Accessory dwelling units
may not be established until the principal residence is constructed on the property.
22C.185.020 Accessory dwelling unit standards.
In the zones in which an accessory dwelling is listed as a permitted use, the community
development director or designee shall review all proposals to establish an accessory
dwelling unit. The following standards and regulations shall apply to all proposed accessory
dwelling units:
(1) On each lot developed with a single-family residence, accessory dwelling units may
be constructed subject to the standards set forth in Table 1 below. An accessory
dwelling unit may not be located on a lot on which a temporary dwelling, as defined
in Chapter 22C.110 MMC, is located.
Table 1
Principal Dwelling Unit(s) Single family residence Middle Housing
Number of Accessory
Dwelling Units Allowed Per
Lot 1
Two (2) Two (2) if the lot allows for
a density of four (4)
dwelling units per lot
pursuant to MMC
22C.010.080. Note: The
accessory dwelling unit(s)
apply to the total allowed
unit density for the lot.
Owner Occupancy
Requirement for Principal
Dwelling or Accessory
Dwelling Units
None
Allowed Accessory Dwelling
Unit Configurations
a) One attached unit and one detached unit;
b) Two attached units; or
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c) Two detached units, which may be comprised of
either one or two detached structures.
Use as Short Term Rental Prohibited
Minimum Size per
Accessory Dwelling Unit 2
200 SF gross floor area
Maximum Size per
Accessory Dwelling Unit 2, 3
1,000 SF gross floor area or 50 percent of the total floor
area of the single family residence, whichever is greater;
provided that, in no case shall an accessory dwelling unit
exceed 1,200 square feet1
Maximum Bedrooms per
Accessory Dwelling Unit
Two (2)
Front setback See MMC 22C.010.080 for standard lots and MMC
22G.080.080 for PRD lots.
Side setback 5 feet
Side street setback 10 feet along non-arterials; 15 feet along arterials
Rear yard setback 15 feet; provided that, the rear yard setback may be
reduced to 10 feet for one-story structures, or for
structures located in a PRD 5
On-lot structure separation A minimum of five (5) feet of separation is required
between structures; provided that, this separation may
be reduced if:
(a) Adequate fire rating is provided between structures
per the International Building Code; and
(b) A 44-inch-wide paved pathway that is free of
obstructions is provided between structures to ensure
adequate access for emergency services.
Building, and Impervious
Coverage
See MMC 22C.010.080 for standard lots and MMC
22G.080.080 for PRD lots.
Height 30 feet
Parking 6 See parking for Middle Housing in MMC
22C.130.030 Table 4.
1 On any lot that meets the minimum lot size required for the principal dwelling unit.
2 Floor areas shall be exclusive of garages, porches, or unfinished basements.
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3 The community development director is authorized to conditionally allow an attached
accessory dwelling unit greater than the maximum size limit within existing structures,
when a denial of such an increase would result in an unreasonable division of interior
space between the ADU and the primary dwelling unit.
4 Existing structures, including but not limited to detached garages, may be converted to
accessory dwelling units, even if they do not comply with current code requirements for
setbacks or building coverage.
5 Detached accessory dwelling units may be built at a lot line, if the lot line abuts a public
alley.
6 No parking areas other than driveways may be in front yards. When the property abuts
an alley, parking areas must be accessed from the alley.
(2) The architectural character of the single-family dwelling shall be preserved. Exterior
materials, roof form, and window spacing and proportions shall match that of the existing
single-family dwelling. In no case shall a detached accessory dwelling unit have axles or be
on a chassis.
(3) The city may not prohibit the sale or other conveyance of a condominium unit
independently of the principal structure solely on the grounds that the condominium unit
was originally built as an accessory dwelling unit.
(4) The provisions of this section do not apply to portions of lots designated with critical
areas or their buffers as designated in RCW 36.70A.060, or to lots in a watershed serving a
reservoir for potable water if that watershed is or was listed, as of July 23, 2023, as
impaired or threatened under section 303(d) of the Federal Clean Water Act (33 U.S.C. Sec.
1313(d)).
(5) In addition to the conditions that may be imposed by the community development
director, all accessory dwelling units shall also be subject to the condition that the use shall
be discontinued if:
(a) The accessory dwelling unit is substantially altered and no longer conforms with
the plans approved by the community development director and the building official;
or
(b) The subject lot ceases to maintain the required parking spaces outlined in MMC
22C.130.030 Table 4.
If the deficiencies outlined in subsections (a) and (b) are remedied, the community
development director may allow the use to be reestablished.