HomeMy WebLinkAboutPlanning 2018-02-15 COMPLETE AGENDA PACKET - ACCESSORY DWELLING UNIT (ADU)City of Tukwila
Department unity Develop ent- Jack Pace Director
Allan Ekberg, ayor
CHAIR, NHAN NGUYEN; VICE -CHAIR, DENNIS MARTINEZ; COMMISSIONERS, MIGUEL
MAESTAS, SHARON MANN, MIKE HANSEN, LOUISE STRANDER AND HEIDI WATTERS
PLANNING COMMISSION
MEETING AGENDA
FEBURARY 15, 2018 - 6:30 PM
TUKWILA CITY HALL COUNCIL CHAMBERS
I. CALL THE MEETING TO ORDER
II. ATTENDANCE
III. ADOPTION OF 1-25-18 MINUTES
IV. CASE NUMBER: L17-0067, Accessory Dwelling Unit Regulation Update (ADU)
APPLICANT: City of Tukwila
REQUEST: Update of regulations for ADUs including allowing detached
ADUs with design and height requirements, lowering the lot size
requirement, modifying the parking requirement, removing ADUs
as accessory uses in non-residential zones, limiting rental of ADUs
to periods of 30 days or more and providing an amnesty period for
existing ADUs.
LOCATION: Citywide
V. DIRECTOR'S REPORT
Tukwila Ci i Hall ► 6200 Southcenter Boulevard Tukwila, 6+A 88118 206-433-1800 a W bsite: TukwilaWA. ov
City of Tukwila
PLANNING COMMISSION
PUBLIC HEARING MINUTES
Date: January 25, 2018
Time: 6:30 PM
Location: Council Chambers
Planning Commission
Present: Chair, Nhan Nguyen; Vice Chair, Dennis Martinez; Commissioners, Miguel Maestas,
Mike Hansen, and Louise Strander
Absent: Commissioners Sharon Mann and Heidi Watters
Staff: Nora Gierloff, Deputy Director, Carol Lumb, Senior Planner; Andrea Cummins,
Urban Environmentalist, and Wynetta Bivens, Planning Commission Secretary
Chair, Nguyen called the public hearing to order at 6:35 PM. Commissioner Nguyen thanked
Commissioner Maestas for doing a wonderful job as the 2017 Chair.
Adoption Commissioner Stander requested am
of Minutes: questions that she raised at the 12/14/
the minutes.
ents to theminutes to include several
ork session. Staff requested one addition to
Commissioner Hansen made a motion to adopt the 12/14/17 minutes as amended to
include the eight questions listed below that Commissioner Strander asked at the
meeting, as well as staff's addition. Commissioner Martinez seconded the motion. All
were in favor.
The addition to the minutes are as fo
1) What is the difference between an exemption and an exception?
Staff: An exemption is a circumstance when the tree regulations are not applicable. An exception is
similar to a variance. If there are some special circumstances that make it difficult or impossible to
meet the requirements of the tree code this process is used to allow flexibility.
2) How is the City going to fulfill GM. goals to encourage more single-family and multi -family
housing while preserving the tree canopy?
Staff: It i balancing act. The code requires to the extent possible trees be retained on site.
For multi-fari)y development, defer to the Landscaping Code, most of the site would probably
be cleared, although ifpossible to retain trees is encouraged. Otherwise, the landscaping code
would specify the am nt of landscaping required on the front, sides and rear. For individual
single-family development there is no requirement for landscaping. For subdivisions, try to
preserve the trees that can be incorporated into the development, otherwise there are street tree
requirements for subdivisions, and requirement for replacement trees in sensitive areas. Also,
try to maintain some protection of the trees on the older homes that currently exist to get to our
goals.
2
3) The proposed regulation states a person can remove four trees that are four to eight inches in
diameter — what if a property only has four trees and they remove them all, how does that keep the
tree canopy?
Staff: it doesn't. But we decided it wasn't reasonable to say that no trees can be removed from a
single-family site. A property owner can remove up to four trees in a three-year period; if more
than four trees are removed, then tree replacement would be required. This would replace some of
the tree canopy. Some jurisdictions are more restrictive, but we felt that coming from our current
regulations going to that extreme, that would be too much.
4) How much is a tree permit, how often does it increase, and what is the enforcement for not getting
a tree permit?
Staff: currently $1.16.55; the price increases annually; we try tp approach enforcement on an
educational basis first; enforcement begins with a courtesy letldr requesting compliance and then
escalates as needed.
5) Is there a plan if the tree canopy falls below 47%
Staff: Not currently.
6) Is it correct that a residential home owner can prune a tree up to 25% and other trees up to 20%,
and no permit is required?
Staff: Yes, it's 25% of the canopy other Than fruit trees; no permit is required for pruning.
7) Which City Department is responsible for doing the canopy assessment in the parks or the public
right-of-way; would the condition of the tree also he assessed`
Staff: It is primarily DD, partnerib with the Parks and Recreation Department. The condition of
the tree is a separate assessment, regarding defects or health concerns. Green Tukwila Partnership
is helping with maintenance with Park properties, currently with Tukwila Park. In the past, City
received a grant from the Washington Dept. of:Natural Resources for its initial tree canopy
assessrncnt, curs n King Conservation Districtis carrying out a canopy assessment for south -end
cities. In the future, e, hope to develop a Citywide maintenance plan for City -owned trees — we
need data from tree inventory to develop the maintenance plan.
8) Is a laurel considered a tree?`
Staff: The laurels are an invasive species. We would also consider it a hedge/shrub rather than a
tree, although it can grow tall, like a tree. A laurel can be removed without penalty or a permit.
Staff also had an addition to the draft minutes to note the discussion from the Commission that the City
needs to provide canopy coverage assessment for City owned properties, City campus and City parks.
Carol Lumb, Senior Planner, Department of Community Develop (DCD), gave the presentation,
Items in the packet responding to past requests and public comments:
• Request for a chart that identifies other jurisdictions and how they treat trees in terms of how
they start regulating (Attachment H)
Page 2 of 9
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• The City Attorney provided guidance on the questions regarding liability (Attachment F)
• Information from the Public Works Department regarding the responsibility for taking care of
trees that are in the public right-of-way (Attachment G)
• Comments from Vern Meryhew, citizen, (Attachment I)
• a comment letter from Greg and Vanessa Zaputil (Attachment J)
• Chart of comments received and request for changes in the Tree Regulation
Highlights given on the Tree Regulations:
• These regulations affect primarily single-family residential ho
shoreline jurisdiction or a wetland, a steep slope, a stream or th+
• The City does not currently regulate the removal of trees
are adjacent to or within a sensitive area.
• We are looking at the Tree Regulations because o
(listed in attachment C)
• The tree canopy for commercial, industrial and multi -family properties will be addressed
through the Landscaping Code.
• The amount of canopy for each of the zoning districts in the City, is taken from the City's tree
canopy assessment prepared in 2012. The low-density csidential districts comprise
es
hat are outside of either the
buffers.
amily property unless they
e Comprehens
vc Plan tree canopy goals.
approximately one third of the zoned area in the City, and the canopy
59%. Because it was so high, the decision was made not to increase
on the Comp Plan goal nt but to maintain the curre2174,43 tree canopy i
• Once the City Council adopts the new Tree Regulations the Departm
Development will work on handouts for educational purposes.
• A Tree permit: w ldl he required when doing work in a critical root zone; pruning a heritage
xistin crown for he removal of trees over 8" in diameter;
if
makes up approximately
tree canopy when working
n the City.
ent of Community
tree more than 2O% of the e g t ,
removing more that the number of trees- allowed m a 36 -month period; or when trees are
illegattyctved.
• ?hen tree replat ement i rdquired, the number of replacement trees is based on the size of the
tree canopy. Hazard or defective trees are not required to be replaced, there is some suggested
l guage to add to the: egulation for clarification —staff will address later.
• Arborist reports are not required for removal of trees on single-family properties, which was a
changeade by the Plararing Commission. It is required for •
removal of her trees, or if
development is on a sits where heritages trees are in close proximity, and for proposed
development, which are primarily for subdivisions or short plats greater than four lots.
Commissioner Stander asked the following additional questions at tonight's meeting that she
requested be included in the minutes.
Question regarding the January 11, 2018, packet, staff report prepared December 28th, attachment E —
Goal 4.13, Page 49 of the January 25, 2018 packet. Residential zone is not listed there, is it somewhere
else?
Staff: The last paragraph was left off on page 35, which should read, "no net loss of canopy cover in
individual categories as listed below: Low Density Residential: maintain current Citywide coverage of
47% and Medium and High Density Residential maintain current Citywide coverage of 40%."
Page 3 of 9
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REQUESTED CHANGES/CORRECTIONS
Planning Commission, from December 14, 2017 work session:
• Page 11 Nuisance Trees, add, underground utilities
• Page 18, 18.54.030D, bring language into consistency, Table A, strikeout the word,
`exceptional'
• Page 18, 18.54.040 A., spell out the letters CRZ, `critical root zone
• Page 19, 18.54.040 Table A, delete the language," an arborist report be prepared for the
removal of trees 18" or greater in diameter."
• Page 21, 18.54.060 D., revised language, "If the number otrees to be removed exceeds the
permitted amount in a 36 -month period on a proper zoned Low Density Residential and
improved a single-family dwelling, those trees shall be replaced based on the replacement
requirements set forth TMC 18.54.080 and Table B."
• Page 23, 18.54.080 B., Sentence added, "Trees damaged due to natural disasters such as wind
storms, hail, ice, snow storms and earthquakes are not required to be replaced."
• Page 25, 18.54.100 D., addressing liability question, liability memo from the City's attorney,
page 54 (attachment F). Liability is vy site and fact specific.
Robin Tischmak, Engineer, Public Works Department addressed questions from the Commissioners
regarding trees in the public right-of-way. DCD and PW Departments are working together on
language in Title 11, which covers the right-of-way to alleviate the conflicting information. One
provision says that abutting property owners shall Maintain vegetation in the public right-of-way unless
the City has accepted maintenance of the vegetation. If a property owner plants a tree in the public
right-of-way in a landscape strip, it requires approval rom Public Works; they issue tree permits and
permit plantings in the public right -o way. e want to make sure that the tree won't present problems
in the future (wrong type of tree) or that there aren't plans to expand the street that would require tree
removal in the future. if the property owner plants the tree the City could accept ownership. If the
property owner has requested and, plants the tree, then maintenance would probably be put on the
property owner.
It's a gray area and specific to the situation. If trees are on private property and causing damage to the
sidewalk the City will go to the property owner and expect them to resolve the problem. If a tree is on
the property line orcin the right-of-way generally the City has taken responsibility in correcting the
issues.
Commissioner Strander inquired on the permitting process for a tree in the right-of-way — does DCD
issue it? Mr. Tischmak said the permit process is a coordinated effort between DCD and Public Works,
but Public Works issues the permit.
Commissioner Strander asked about trees planted in residential areas. Mr. Tischmak responded that
it is a changing situation, but in the past, Public Works has not planted trees in the right-of-way in
residential areas. Often, to install the public improvements, like sidewalks, trees must be removed
from private property. In that case, then Public Works will work with the property owner to replace
these trees. Commissioner Strander cited the example of the City maintaining trees in the right-of-
way near her property. It was not clear which department of the City might be maintaining these trees.
Page 4 of 9
5
In response to a question raised by Commissioner Nguyen, staff stated that the violation section of the
code was added in the event people cut down trees they are not supposed to. The code allows the City
to assess a fine up to $1,000, or 3 times the market value of the tree as penalty for the violation. The
Director has the authority to seek or not to seek a financial penalty in addition to the required
replacement of the trees. Mr. Tischmak stated it is a different issue if the tree is cut down in the right-
of-way, in addition to whatever penalties would be assessed by DCD.
There was a discussion about an example of deliberate tree removal in Seattle to improve views and a
comparison with Tukwila's proposed regulations.
Commissioner Martinez requested that when revisions to the SAO rcgulations are brought to the
Planning Commission, these include more specific violation languat
The question was raised regarding past issues with insects damaging trees. Staff responded that the
tree code doesn't have any bearing on that type of situation. This was probably the U.S.D.A. or State
Department of Agriculture that required the tree removal in order to prevent an infestation of an
invasive species — these agencies would have compensated property owners. Tree removal in this
instance would be an exemption from the tree code.
Question raised, page 33, 18.54.120 B enforcement of a p
Chapter and the explanation going to City Council.
ner threatening to violate the
Staff: If it was a serious situation and time sensitive special emergency, the code allows the director to
go to court without going to the City Council beforehand. There would be coordination with the City
Attorney, and Council Presiden7
Public Works Depa
commendations:
• Page 17, 18.54.030 C., 3., revised language to include, "routine maintenance within rights-of-
way related to interference; site distance emergency or topping as codified in chapter 11.20 of
the TMC also be exempt, ' which will make the two chapters consistent.
Add, a new number five, under Exemptions to read: "The removal of trees in the right-of-way
dated to a capital project that has a landscaping component that includes trees, where there is
adequate room in the right-of-way."
Vern Meryhe
zen, recommendations:
• Page 60, remo , City of Lake Forest Park' from the definition
• Page 12, revise the language to read, an individual who is a certified professional with
academic and/or experience that makes them a recognized expert in urban forestry and tree
protection.
• Increase significant tree size to 6". Commissioner Martinez suggested approving the
recommended 6". Staff will change the definition of Significant Tree and in Table A and any
references of 4 inches to 6" throughout the draft regulations. There was discussion on the
approach of other jurisdictions, particularly SeaTac, which distinguishes between a conifer and
deciduous tree in setting the significant tree size.
Page 5 of 9
6
Staff went over the comments and questions from Greg and Vanessa Zaputil, citizens, expressed in
their comment letters, dated 1/10/18 and 1/24/18, and responded to questions from the Commission.
Some of the questions have been addressed through questions asked by the Planning Commissioners
and will not be repeated below. Responses are summarized below:
• For non -single-family residential properties, the landscaping code applies, rather than the tree
regulations. Typically addressed through the development process.
• Property owners are not required to use a contractor — they can take out trees themselves if
desired;
• The information needed for a tree permit will depend on the complexity and extent of the
proposed tree removal — staff works with an applicant to help address which criteria must be
addressed and which can be skipped and typically a landscape architect would not be required
for tree removal. Commissioner Hansen said do not add a lot of requirements and put too
many burdens on the citizens when removing trees
• The proposed regulations are not based on property size — this is for ease of administration and
clarity of application for property owners. Other
felt it was not the best one for Tukwila.
• Education of property owners on proper tree pruning techniques will be important — there are
videos on the City's web site on this, staff will prepare other materials.
• Healthy trees can be removed — a tree per nit would not be denied because a tree is healthy.
urisdictions have used this approach, but staff
For the record, a second letter from Greg and Vanessa Zap )l, dated January 24, 2018,.was submitted
and requests cost estimates for property owner for items they identify as being required. Some of this
is based on a contractor being hired that person will determine how much it will cost to remove a
certain sized tree. Same for an arborist the fee charged is up to the arborist. Property owner is not
being required to hire an arborist (except in the circumstances already identified). For site plans, we
work with an applicant to develop the site plan - hiring a landscape architect is not required. Tree
replacement i based on the canopy lost, but City doesn't specify the type of tree to plant other than the
canopy
Co
is needed to remove a volunteer tree?
Staff: A volunteer tree, such as a cottonwood, that grows in your yard will probably be removed before
it gets to be 6 -inches in size - but if it is larger, then will count towards the up to four trees that can be
removed in a 36 -month period.
Does the City follow up to see if a tree was removed?
Staff: Typically, no, staff does not go out to see if a tree has been removed, unless the property owner
was required to replant after removal or if there was concern about infrastructure around the tree to be
removed.
Damaged trees from natural events (storms etc.) do not require a tree permit?
Staff: These trees are exempt.
Page 6 of 9
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Staff recommended revisions:
• Revise references to ISA Certified Arborist in the code to, "Qualified Tree Professional"
• Page 18, 18.54.040, revise #3 to read, Professional review or recommendation. "In certain
circumstances, the Director may require professional review or recommendation.
This assessment, prepared by Qualified Tree Professional should address the following."
• Page 23, 18.54.080 a, revise language of first sentence to read, ` Each existing significant tree
removed, above the number allowed in Table A, including the removal of trees in easements
and rights-of-way for the purposes for constructing public streets and utilities, shall be
replaced with new tree(s), based on the size of the existing tree as shown below, up to a
maximum density of 70 new trees per acre, generally 12 to 15 feet apart."
• Page 23, 18.54.080 B, new sentence added at the end: "Trees determined to be defective by the
City or a Qualified Tree Professional are not require to be replaced.
Staff requested confirmation that they have permission td make the changes, as discusedaby the
Commission and move the draft regulations on to the City Council.
Commissioner Martinez, said looking at the comparison cif other cities and whether permits are
required that involve a fee, that he was concerned with public outreach and the impact on the new tree
canopy survey and fees required. He said that the City needs to make the public aware that the first
three trees removed are free, then a fee -permit is requiredt lie said it cores at significant financial
impact to the community.
There were no public
The public hearing was e
DELIBERAT'IO
Chairman Nguyen asked i
draft reiulatic ns?
sioners have any comments, are they ready to take action on the
Commissioner Strander read the following:
"The Comprehensive Plan goal 4.13 talks about no net loss of canopy cover in individual zoning
categories. So Low Density Residential, they want to maintain a 47% canopy coverage. Medium and
High Residential, Citywide coverage of 40%. I think the intent of the regulations set forth in the tree
ordinance are meant to accomplish this goal of the tree canopy. However, I believe these regulations
may not attain this goal. In order for the City to encourage and allow for more housing to be built, the
likelihood of a diminished tree canopy is imminent, especially given scarcity of buildable land in the
City of Tukwila. The requirement for a 47% tree canopy in a Low Density Residential zone and 40%
tree canopy in medium and high Density Residential zones will be very difficult if not impossible to
achieve with housing infill and redevelopment. I feel there is not really a way to keep the
aforementioned tree canopy presented goals and build expected number of housing units needed,
anticipated, or required. So, for these reasons I will not support this ordinance and will be voting no."
Page 7 of 9
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Commissioner Maestas asked Commissioner Strander if there was a recommendation she would
make in order to meet it and support the tree regulations?
Commissioner Strander said she thinks it would take some more time but she is not really sure.
Staff said that the next few years will allow them to see how we measure up with the tree canopy
assessment once they have some more data. When there is more data, this will show if the City is
falling short and how best to address this if the City is falling short.
Commissioner Nguyen said that he agrees with Commissioner Strande
does feel comfortable moving forward, with the amendments so fa.
could keep in mind to revisit this issue in the future.
ith the need for data, but he
ng a balance. He said we
Commissioner Hansen said there are two different issues or him, a new policy and the Growth
Management Act Policy, and he does not see the intersection clearly on those. He said they do not
have current data, but from a policy stand point he's ok with the policy they worked on, He asked if
there was an urgency to get this done before the next data is obtained, at which time they would have
something clear to work off. He asked if 2012 was the first: year the City had canopy data. He said he
accepts the policy but shares the concern abaut how it ties into the Growth Management Act.
Staff said 2012 is the beginning point for canopy assessment data.
Commissioner Martinezsaid one o theways they could look at t as a Planning Commission is that
they have a lot of development that is going to happen in the next several years. He said that the
Commission as well as staff are going to have to look at not foregoing or allowing some of the
development to get a variance on the canopy growth. It's one way to help protect the future with the
development. He is concerned bsaid they must start somewhere and they will make sure that
future development has the proper amount of canopy coverage as required with no variance.
Commissioner Maestas said this is a policy that would support the goal of Comprehensive Plan
canopy the goal being achieved. He said there is no guarantee that it will be accomplished but he sees
it as something that is going toincrease and maintain canopy. Without this policy having much more
restrictive elements related to cutting down trees or related to housing and business development, he
doesn't see those restrictions being part of this policy. He said he thinks this policy focuses on the City
doing everything they can to maintain existing trees. He asked that when they are looking at the data
to give some thought as to how the City can promote the addition of trees by offering incentives for
homeowners to make an assessment on their property of where they can add trees to their property. He
suggested encouraging homeowners to add trees to their property and take a positive role in increasing
the overall canopy of the City. He asked if there is something they could add to the policy to increase
new trees in the City.
Staff said that the draft regulations do allow using the tree replacement fund for single-family property
owners to have a free street tree with the concurrence of the Public Works Department. Staff can look
at other ways for trees to be planted and encouraged.
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Commissioner Nguyen suggested asking the Council to set aside some money when they complete the
bi-annual budget for the Parks and Recreation Department for an initiative for planting trees. The
Planning Commission could direct the chair to do this if they would like. He said it would be another
opportunity.
MOTIONS:
Commissioner Hansen made a motion to approve 18.06 for the Definitions, as revised.
Commissioner Maestas seconded the motion. Motion carried.
Commissioner Hansen made a motion to approve the changes as revised for TMC 18.54 Tree
Regulations. Commissioner Martinez seconded the motion. Motion carried four in favor,
Commissioner Strander opposed.
DIRECTOR'S REPORT:
• Accessory Dwelling Units on the PC agenda, February
• Staff reminded the Commission to verify their attendance the day prior to meetings to make
sure there is a quorum.
ADJOURNED:
Submitted by:
8:50 PM
Wynetta Givens
Planning Commission Secreta:
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City of Tukwila
Allan Ekbet
Department of Community Development — Jack Pace, Director
INFORMATIONAL MEMORANDUM
To: Tukwila Planning Commission
From: Nora Gierloff, Deputy DCD Director
Date: January 29, 2018
Subject: L17-0067 Accessory Dwelling Unit Code Amendments
Background
In March 2017 the City Council held a Housing Policy Work Session and considered a variety of housing
related actions. One of the items that the Council prioritized for policy consideration was an update to
Accessory Dwelling Unit (ADU) zoning standards to be followed by an amnesty program for existing
units. The intention was to create additional housing options and address the life safety issues in the
many illegal ADU conversions in the City.
At the October 26, 2017 public hearing the Planning Commission chose from a variety of proposed
policy changes related to Accessory Dwelling Units (ADUs). Staff has prepared a draft of the code
changes in strikeout/underline to codify those policy choices along with other suggested edits.
The City performed an environmental review (SEPA analysis) on this non -project action to amend the
Zoning Code with the proposed ADU changes and issued a Determination of Non -Significance (DNS) on
January 24, 2018.
Discussion
The policy direction set by the PC in October is summarized as follows:
1. Allow detached ADUs under the following conditions:
• Not allowed if there is an attached ADU on site (only 1 ADU per parcel)
• Unit may be up to 1,000 square feet (must still meet the existing standards for total building
footprints of 2,275 sf and maximum impervious area of 4,875 sf for a 6,500 sf lot, see sample
site plans at Attachment B)
• Detached units must be set back at least as far from the street as the main house. This would
not apply to the second front of a through or corner lot, or where the unit is incorporated into
an existing structure such as a detached garage.
Tukwi%a 'iffy H 6200 Sou center aui v rd • Tukwila, WA 98188206433180O a Website: Tukwiil A.gov
12
PC ADU Review
Page 2
• Limit height to 20 feet except for apartments built over a garage which may be up to 25 feet
tall. Building height is calculated from the mid -point of any elevation change across the
footprint of the house to the mid -point of the pitched roof.
2. Increase the percentage of the house that can be occupied by an attached ADU from 33% to
40% up to a maximum of 1,000 SF, whichever is less.
3. Reduce the lot area requirement from 7,200 square feet to 6,500 square feet for both
attached and detached ADUs.
4. Retain the owner occupancy requirement for 1 unit on site, either the house or ADU.
5. Retain the requirement that ADUs up to 600 SF are required to have 1 off-street parking space
while units over 600 SF are required to have 2 additional spaces. However, allow a waiver of
the second space for ADUs over 600 SF if the ADU is located on a block with on -street parking.
6. Provide a 1 -year amnesty period for registration of illegal ADUs and allow owners to request
flexibility from the Director for the following standards:
• Exceeding the permitted height for a detached ADU
• Exceeding the permitted area for an attached or detached ADU
• Not providing a second parking space for an ADU over 600 sf in area, if required
• Roof pitch of less than 5:12
• Location of the ADU on the lot.
Owner occupancy, providing at least 1 parking space per ADU, and meeting the 6,500 SF
minimum lot size would not be waived.
7. Do not create a residential occupancy limit in the Zoning Code but continue to enforce the
International Building Code occupancy load of 200 square feet per person.
Additional Changes
Staff suggests adding a definition of ADU to the Zoning Code for clarity. We currently have definitions
of dwelling unit, single-family dwelling, and multi -family dwelling. This change has been included in the
draft changes at Attachment A.
Currently ADUs are allowed as accessory uses in the following Zoning Districts:
• Low Density Residential,
• Medium Density Residential,
• High Density Residential,
• Office,
• Residential Commercial Center,
• Neighborhood Commercial Center,
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PC ADU Review
Page 3
• Regional Commercial,
• Tukwila Valley South, and
• Tukwila South Overlay.
During the environmental review process it was proposed to remove ADUs as an accessory use in the
non-residential districts 0, RCC, NCC, RC, TVS and TSO because they must be accessory to an owner -
occupied single-family house. Allowing additional residential uses in these zones would increase
incompatible uses and environmental impacts such as noise. This change has been included in the draft
changes at Attachment A.
Staff suggests that ADUs be limited to rental periods of 30 days or more and be subject to the
Residential Rental Business License requirements. This is consistent with the current standard for
multi -family units and meets the policy goal of creating additional housing options for Tukwila
residents. This change has been included in the draft changes at Attachment A.
Comprehensive Plan Goal 3.2
The City of Tukwila has safe, healthy and affordable homes for all residents in Tukwila.
Policy 3.2.2
Encourage a full range of housing opportunities for all population segments, including very low-income
households earning less than 30% AMI, through actions including, but not limited to, revising the
Tukwila zoning map and development codes as appropriate, which would enable a wide variety of
housing types to be built.
Implementation Strategy
• Following the neighborhood outreach process, consider allowing a detached accessory dwelling
unit in the Low -Density Residential zone on all lots that meet the minimum lot area, when
various appearance and performance criteria related to impacts on adjacent properties are
satisfied.
Recommendation
Forward the proposed code changes with or without amendments to the City Council for adoption.
Attachment
A. Draft ADU Code Changes in Strikeout/Underline
B. Sample Site Plans with Detached ADUs
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Draft Tukwila ADU Updates Reflecting PC Policy Direction
New Definition
18.06.016 Accessory Dwelling Unit
"Accessory dwelling unit" means a dwelling unit that is within or attached to a single-family dwelling or
in a detached building on the same lot as the primary single-family dwelling. An ADU is distinguishable
from a duplex by being clearly subordinate to the primary dwelling unit, both in use and appearance.
Amended Section
18.50.050 Single -Family Dwelling Design Standards
All new single-family dwellings, secluding as well as taccessory snivelling units land other accessory
structures that require a building permit, must:
1. Be set upon a permanent concrete perimeter foundation, with the space from the bottom of the
home to the ground enclosed by concrete or an approved concrete product that can be either load
bearing or decorative.
2. If a manufactured home, be comprised of at least two fully -enclosed parallel sections, each of not less
than 12 feet wide by 36 ifeet long.
3. Be thermally equivalent to the current edition of the Washington StateLs eEnergy ECode with
amendments.
4. Have exterior siding that is residential in appearance including, but not limited to, wood clapboards,
shingles or shakes, brick, conventional vinyl siding, fiber -cement siding, wood -composite panels,
aluminum siding or similar materials. Materials such as smooth, ribbed or corrugated metal or plastic
panels are not acceptable.
5. Have the front door facing the front or second front yard, if the lot is at least 40 feet wide. This
requirement does not apply to ADUs or accessory structures.
6. Have a roofing material that is residential in appearance including, but not limited to, wood shakes or
shingles, standing seam metal, asphalt composition shingles or tile, with a minimum roof pitch of 5:12
New Section
18.50.220 Accessory Dwelling Unit (ADU) Standards
A. General Standards
1. ADUs may only be built on lots that meet the Minimum lot size required in the Zoning District
they are located within.
2. Only one ADU, either attached or detached, is permitted per parcel containing a single-family
house.
3. Attached units may occupy a maximum of 40%lof the square footage of the primary residence
(including an attached garage) or up to 1,000 square feet, whichever is less.
Commented [NG1]: This new definition emphasizes that
the unit is accessory to a niain house,
Commented [NG2]: This applies the same design
standards to ADUs as currently apply to single family
--- Commented [NG3j: This results in an 864 square fo0t.
house, so a manufactured home could be used as a
detached ADU if it meets all other requirements
Conitnented [NG4]: This would reduce the lot size
required for an ADU from 7,200 to 6,500, the minimum in
the LDR Zone.
16
Page 2
Draft ADU Changes
4. Attached units created through additions to the primary residence shall be consistent with the
roof pitch, materials and window type of the existing structure.
5. Detached units may be a maximum of 1,000 square feet. If built over a detached garage the
garage area would not count toward this size limit.
6. Detached units may be up to 20' feet lin height, except that an apartment built over a detached
garage may be up to 25 feet in height.
7. Detached units must be set back at least as far from the street as the main house. This does not
apply to the second front of a through or corner lot or where the unit is incorporated into an
existing structure.
8. The ADU may not be sold as a condominium or otherwise segregated in ownership from the
primary residence.
9. i ADUs may not be rented for periods of less than 30 days;.
B. Parking
1. One off-street parking space must be provided for ADUs less than 600 square feet in area,
and two spaces for units over 600 square feet].
2. The second ADU parking space is not required if the parcel containing the ADU can be
accessed from a street that has legal on -street parking.]
3. These ADU spaces are in addition to any parking spaces required for the primary residence.
4. Tandem spaces are permitted.
C. Owner Occupancy Requirement
1. lAs Person who owns at least 50% of the property must physically reside in either the ADU or
the primary residence. The owner's unit may not be rented to another party for an eriod
of time.
2. The owner must provide documentation of their occupancy such as a vehicle or voting
registration. Falsely certifying owner occupancy or failure to comply with the residency
requirement shall result in the loss of ADU registration and penalties per TMC 5.06.
3. The owner or owners must sign and record an affidavit on forms provided by the City
acknowledging that this requirement shall run with the land.
4. If the owner occupancy requirement is violated an owner shall either:
a. Re -occupy one of the units, or
b. Remove the elements of the accessory dwelling unit that make it a complete,
separate unit.
D. Failure to comply with any of the requirements of this section shall be subject to enforcement and
penalties as prescribed in TMC Chapter 8.45 and the issuance of a Notice of Violation and Order in
accordance with TMC 8.45.070.
New Section
18.50.230 Accessory Dwelling Unit (ADU) Registration Procedures
A. To gain approval to establish an ADU, a property owner shall submit a registration form, sign
and record an affidavit of owner occupancy and obtain a building permit for any necessary
remodeling or construction.
17
Commented [NG6]: The PC recommended allowing
detached ADUs subject to the following standards.
Commented [NG7]: The overall height limit in LDR is 30
feet.
Commented [N 8] This is consistent with the cur
standard for multi -family units. Other types of short
rentals (spara bedrooms, boarding houses) will be
addressed in a separate set of code amendments
Commented''[NG9]: This is our current standard. Soi
jurisdictions only require 1 pace per ADU. Another op
wo ldbetorequire1spac per bedroom.
Commented [NG10]: The PC added this flexibility.
Commented [NG11]: This is the current standard
Page 3
Draft ADU Changes
B. All ADUs existing prior to the enactment of these requirements shall apply for registration
within one year after the effective date of this codel. Within the one-year amnesty period
existing ADUs may be registered without meeting one or more of the following standards:
a. Exceeding the permitted height for a detached ADU
b. Exceeding the permitted area for an attached or detached ADU
c. Not providing a second parking space for an ADU over 600 sf in area, if required
d. Having a roof pitch of less than 5:12
e. Location of the ADU on the lot.
C. Illegally created ADUs must be brought into compliance with the life safety requirements of the
Tukwila Municipal Code, International Residential Code and International Property Maintenance
Code or they must be removed.
D. If either the primary residence or the ADU will be rented, a Residential Rental Business License
per TMC 5.06 must be obtained prior to occupancy of the unit by a tenant.
Amended Table
Table 18-6: Land Uses Allowed by District
P = Permitted outright; A = Accessory (customarily appurtenant and incidental to a permitted use); C =
Conditional (subject to TMC 18.64); U = Unclassified (subject to TMC 18.66); S=Special Permission
(Administrative approval by the Director)
Commented LNG12J, This is a new regstration
requirement combined with an amnesty period, The go
to address life safety issues rn illegal existing ADUs.
Use
LDR
MDR
HDR
MUO
0
RCC
NCC
RC
RCM
C/L
I
LI
HI
MIC/L
MIC/H
TVS
TSO
Dwelling — Detached
PP
P
P
P
P
P
P
P
Single family (Includes
site built, modular
home or new
manufactured home).
One detached single
family dwelling per
existing lot permitted
in MUO, 0, RCC, NCC,
TVS
Dwelling unit—
A
A
A
Accessory P
Note 17. See 18.50.220 for Aaccessory dwelling unit; standards,
a. minimum lot of 7,200 square feet;
b. accessory dwelling unit is no more than 33% of thc square footage of thc primary residence and
a maximum of 1,000 square feet, whichever is less;
property,
unit, so that both units appear to be of the same design as if constructed at the same time;
c. minimum of three parking spaces on the property with units Icss than 600 squire feet, and a
minimum of four spaces for units over 600 square feet; and
f. the units are not sold as condominiums.
Commented [NGI Thrs change would limit ADUs to
single and multi family zones
Commented [NG14]. Thi ordinance would codify thi
erlteria for ADUs instead of just listing them in a footno
theiUse Table.
18
19
7,200 SF Lot
1,450 SF Footprint for 2
Story House with Garage
Max building footprint 2,457
Max Development Coverage 5,400 SF,
Total this example 3,225 SF
20' front setback. 5' side. 10' rear
Driveway, parking pad
and sidewalks are 800 SF
20
6,500 SF Lot
825 SF Single story ADU
Size limited by Max Footprint
1,450 SF Footprint for 2
Story House with Garage
Max building footprint 2,275
Max Development Coverage 4,875,
Total this example 2,940 SF
20' front setback. 5' side. 10' rear
21