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CITY OF SEATTLE - DETERMINATION OF SIGNIFICANCE (DS) AND REQUEST FOR COMMENTS ON SCOPE OF EIS - Seattle Department of Construction and Inspections

Land Use Information Bulletin

CITY OF SEATTLE - DETERMINATION OF SIGNIFICANCE (DS) AND REQUEST FOR COMMENTS ON SCOPE OF EIS

Conditions:

Project Name: Accessory Dwelling Units Environmental Impact Statement

 

Proponent: City of Seattle

 

Lead Agency: Seattle City Council

 

Project Location: City of Seattle

 

Description of the Proposal: The City of Seattle is proposing to change regulations in the Land Use Code to remove barriers to the creation of accessory dwelling units (ADUs) in single-family zones. ADUs include backyard cottages, known as Detached Accessory Dwelling Units (DADUs), and in-law apartments, known as Attached Accessory Dwelling Units (AADUs). The proposal involves allowing two ADUs on one lot, removing the existing off-street parking and owner-occupancy requirements, and changing some development standards that regulate the size and location of detached ADUs.

 

ADUs have been allowed citywide as part of a single-family house or in the backyard of a single-family-zoned lot since 1994 and 2010, respectively. The City’s action would modify the rules that regulate when and where a property owner can create an ADU. The objective of this action is to remove regulatory barriers to ADU production, increase the number of ADUs constructed in Seattle, and allow flexibility for larger ADUs that could accommodate changing household needs and families with children. These policy changes would affect development in Seattle’s single-family zones.

 

Environmental Determination: In May 2016, the City prepared an environmental checklist evaluating the potential environmental impacts of the proposed changes to the land use code. The environmental determination of non-significance in the checklist was appealed in June 2016. In December 2016, the Seattle Hearing Examiner determined that a more thorough review of the potential environmental impacts of the proposal was required (https://web6.seattle.gov/Examiner/case/W-16-004). Based on the Hearing Examiner’s decision, the Seattle City Council, as the SEPA lead agency, has determined that this proposal may have significant adverse environmental impacts on the environment. An EIS is required under RCW 43.21C.030 (2)(c) and will be prepared. The EIS will address probable significant adverse environmental impacts of the proposed changes to the Land Use Code.

 

Elements of the Environment: WAC 197-11 establishes that EISs shall provide a level of detail commensurate with the importance of the impact. The lead agency has preliminarily identified the following elements of the environment for analysis in the EIS:

 

  • Land Use

  • Aesthetics

  • Transportation, including parking

  • Housing and Socioeconomics

  • Public Services and Utilities

 

Alternatives: The lead agency has preliminarily identified the following alternatives for analysis in the EIS. Table 1 compares these alternatives.

 

  • Alternative 1 – No Action. Under Alternative 1, the EIS will analyze the impacts of development under existing ADU regulations. Attached ADUs (AADUs) are currently allowed inside or attached to the main house on all lots in single-family zones. Detached ADUs (DADUs) are currently allowed in all single-family zones subject to certain criteria, including a minimum lot size and maximum coverage limits. When a property owner creates an AADU or a DADU, the owner must also have an off-street parking space and must reside on the property. Up to eight unrelated people can live on a single-family lot, including the occupants of an AADU or DADU. Both AADUs and DADUs can be used as short- or long-term rentals.

  • Alternative 2 – Removing Barriers to ADU Development. Under Alternative 2, the EIS will analyze the proposed Land Use Code changes under consideration to achieve the objective of removing barriers to the creation of ADUs in single-family zones. Under Alternative 2, a lot could have an AADU and a DADU; no parking would be required; there would be more flexibility for the size, design, and siting of DADUs; and the property owner would not have to live on the property. The current household size limit of eight unrelated people would apply unless a lot has an AADU and a DADU, in which case the limit would be 12. No change is proposed to current City policy allowing AADUs and DADUs to be used as rentals.

 

Table 1. Existing and Proposed Land Use Code Regulations for ADUs

 

Alternative 1 (No Action)

Alternative 2

1

Number of ADUs allowed on a single-family lot

A single-family lot can have one AADU or one DADU, but not both.

A single-family lot can have an AADU and a DADU.

2

Parking

One off-street parking space required for an AADU or DADU unless the lot is in an urban village.

No off-street parking required.

3

Owner-occupancy

An owner must occupy either the main house or the AADU/DADU for six months of the year.

No requirement for an owner to occupy the house, AADU, or DADU.

4

Minimum lot size for DADUs

4,000 square feet

3,200 square feet

5

Maximum square footage

AADU 1,000 square feet, including garage and storage areas

 

DADU 800 square feet including garage and storage areas

AADU 1,000 square feet, excluding garage and storage areas

 

DADU 1,000 square feet, excluding garage and storage areas

6

Maximum height

No change from existing height limits, which vary by lot width and range from 15-23 feet.

Height limits are 1-3 feet higher than existing limits, depending on lot width.

7

Lot Coverage Limit

35 percent of lot area for lots 5,000 square feet and larger and 15 percent of lot area plus 1,000 square feet for lots under 5,000 square feet.

8

Rear yard coverage limit

40 percent of a rear yard can be covered by a DADU and other accessory structures (like a garage). This limit applies in addition to the overall lot coverage limit.

60 percent of a rear yard can be covered by a DADU and other accessory structures, if the DADU is only one story.

9

Location of entries

DADU entrances cannot face the nearest side or rear lot line unless that lot line abuts an alley or other public right-of-way.

DADU entrances can be on any façade, provided it is 10 feet from the lot line if located on the façades facing nearest side or rear lot line (unless abutting right-of-way).

10

Roof features

No exceptions for roof features on accessory structures are allowed.

Exceptions from the height limit are allowed for projections like dormers that add interior space, subject to the same provisions that govern exceptions for single-family houses.

11

Household Size

Any number of related people, or up to 8 unrelated people, can live on a single-family lot, including in an AADU or DADU.

Any number of related people, or up to 8 unrelated people, can live on a single-family lot with an AADU or DADU. If the lot has an AADU and DADU, the limit is 12.

12

MHA Requirements

Mandatory Housing Affordability (MHA) does not apply to creation of ADUs in Single Family zones.

13

Rental Registration and Inspection Ordinance (RRIO)

Property owners renting one or more units, including in Single Family zones, must register for inspections to ensure housing is safe and meets basic maintenance requirements.

 

Scoping: Agencies, affected tribes, and members of the public are invited to comment on the scope of the EIS within the 30-day comment period beginning on October 2, 2017, and closing on November 1, 2017. All comments are welcome, but comments in the following areas are particularly valuable:

 

  • Reasonable range of alternatives

  • Potentially affected resources and extent of analysis for those resources

  • Measures to avoid, minimize, or mitigate effects of the proposed land use code changes

 

All comments are due by 5:00 p.m., November 1, 2017, and may be submitted:

 

  • Online at: seattle.gov/council/adu-eis

  • Via e-mail to: ADUEIS@seattle.gov

  • In writing to: Aly Pennucci, City Council Central Staff, PO Box 34025 Seattle, WA 98124-4025

  • In person at the EIS Public Scoping Meetings/Open Houses:

Meeting Locations:

October 17, 2017, 6:00-7:30 p.m.

High Point Community Center

6920 34th Ave SW

Seattle, WA 98126

October 26, 2017, 6:00-7:30 p.m.

Hale’s Ales (in the Palladium)

4301 Leary Way NW

Seattle, WA 98107

 

These meetings will provide an opportunity to learn more about the proposed land use code changes and provide input on the environmental review process.

 

Date:  October 2, 2017       SEPA Responsible Official:   ___on file_______________

                                                                               Ketil Freeman, AICP

                                                                               City Council Central Staff