This page provides guidance, model ordinances and other resources to assist local jurisdictions in developing middle housing regulations for their communities.
Middle housing is a range of housing types, from duplexes to sixplexes, townhomes, courtyard apartments and cottage housing, intended to be compatible with single-family neighborhoods. The tools provided here are intended to support communities required to include middle housing development options; however, these tools or ideas from these tools may be used by any community looking to include more housing options in their community.
Additionally, accessory dwelling units (ADUs) are required to be provided in every GMA (Growth Management Act) community. While many jurisdictions have adopted ADU regulations, the 2023 legislature provided parameters for how ADUs are regulated, including removing some barriers to development, such as size limitations. The tools provided here guide jurisdictions.
Draft guidance available for public comment
Commerce is seeking public comment on several new planning guidance documents. These fact sheets and guidance are intended to assist local communities in developing their own middle housing ordinances, regulations, and other official controls.
The draft documents include:
- Unit Lot Subdivision Fact Sheet (PDF)
- Residential Parking Fact Sheet (PDF)
- Impact Fees Fact Sheet (PDF)
- Neighborhood Commercial Fact Sheet (PDF)
- Co-Living Guidance (PDF)
Please submit comments using this online form by 5 p.m. on Monday, Dec. 23, 2024.
Public participation webinar Dec. 5
Commerce will host a public webinar to present the Unit Lot Subdivision, Residential Parking Fact Sheets and Co-Living Guidance on Thursday, Dec. 5, 2024 from 10 a.m. – 11:30 a.m.
Register for the webinar (ZOOM)
A recording of the webinar will be posted to the middle housing web page until the end of the comment period. Attendance at the webinar is not required to provide comments.
Middle housing guidance
Middle housing is intended to be compatible with single-family neighborhoods while providing more dwelling units per lot. It supports housing affordability and increases housing stock while generally utilizing existing infrastructure. The following documents replace the prior January documents which can be requested from Commerce.
- Middle Housing Update Deadlines (PDF)
- User Guide for Middle Housing Model Ordinances (PDF)
- Model Ordinance for cities 25,000 and over (PDF)
- Model Ordinance for cities under 25,000 (PDF)
- Middle Housing resources on EZView (EZview.wa.gov)
- Middle Housing Checklist (Word)
For those communities seeking a time extension or the use of an alternative pathway for compliance, please utilize the following. The guidance in the Fact Sheets is interim, until such time the Washington Administrative Code (WAC) update addressing housing bills is adopted in late 2024/early 2025. The adopted WAC will identify the final alternative pathway review and application processes.
While ADUs are not defined as middle housing, they provide beneficial infill housing which fit into residential neighborhoods. Furthermore, two (2) ADUs are required to be permitted on lots within urban growth areas, with some limitations.
ADU resources
Certain residential uses (i.e. middle housing, ADUs, co-living) have standards related to the amount of parking that may be required. In addition, improvements to parking areas that serve residential development are subject to certain requirements.
Empirical parking study guidance
Both Middle Housing and Accessory Dwelling Unit requirements include options for developing an empirical parking study to determine appropriate parking requirements (outside of the requirements of state statute). The following documents provide guidance to local governments in developing an Empirical Parking Study and in making a certification request to Commerce.
Resources
Commerce strives to support your work through providing valuable resources, tools and examples. Please contact us if you need any of the following in an editable format.
Several preemption clauses related to housing development were enacted in the 2023-24 legislative sessions. Refer to the preemptive state laws for infill housing fact sheet (PDF) for detailed information.
Neighborhood infill development guidance is provided to assist cities in proactively understanding public works, engineering, and infrastructure issues as redevelopment occurs. The neighborhood infill development guidance addresses potential barriers to the development of neighborhood infill housing, provides examples of proactive solutions, and provides resources for planners to lead discussions with service providers.
Manufactured/mobile home communities (MHCs) are residential areas that house multiple manufactured or mobile homes with shared infrastructure and amenities.
As communities across the state plan for housing that meets the needs of all income segments, they should take a careful look at this naturally occurring source of affordable housing.
Commerce has prepared the following guide to help local governments consider preserving this housing type.
- General Middle Housing FAQ (PDF)
- Jurisdictions subject to Chapter 332, Laws of 2023 (PDF)
- Middle Housing Building Types (PDF)
- Middle Housing Lot and Block Models (PDF)
- Middle Housing – Introduction (PPT)
- Middle Housing Study (PPT)
- Middle Housing – What, How and Where? (PPT)
- Middle Housing – How Do We Get More? (PPT)
- Middle Housing Summary of Resources (PPT)
- Middle Housing Presentation Videos
- Middle Housing appraiser engagement FAQ (PDF)
- Middle Housing Pro forma: Puget Sound Region Final (Excel)
- Middle Housing Pro Forma: Feasibility Attainability Slides (PDF)
- Middle Housing Pro Forma: Presentation Recording
- Appendix A: Middle Housing Market Assessment (PDF)
- Appendix B: Pro Forma Calibration and Assumptions (PDF)
- Appendix C: Middle Housing Pro Forma User Guide (PDF)
- Appendix D: Middle Housing Sensitivity Testing (PDF)