SF4123

Purpose

This bill aims to limit how local governments control housing through zoning and to expand housing options. It would require municipalities to permit and streamline several housing types (including small multifamily and accessory units) and to remove many local design and parking barriers. It also sets rules to accelerate approvals, increase density in some areas, and share information about compliance.

Key terms defined

• Accessory dwelling unit (ADU): a second dwelling on the same lot as a single-family home, built to code and allowed even if family status changes.
• Bulk control: rules about size, shape, and placement of buildings.
• Greenfield lot: land zoned for residential use that is undeveloped or newly platted after June 1, 2026.
• Mixed housing: housing types including duplexes, triplexes, quadplexes, and townhomes.
• Multifamily residential development: a building with multiple dwelling units (e.g., a building with many apartments).
• Multifamily affordable housing development: multifamily units that are income-restricted or have a covenant to stay affordable for many years.
• Residential unit: a dwelling used for living purposes by a single owner or tenant.
• Townhouse: a group of attached homes, each serving as a separate dwelling unit.
• Single-family home: one detached dwelling on a lot.
• (Others include “municipality,” “request,” “mixed housing district,” and “commercial districts.”)

Main provisions

• Applicability and process

  • Municipalities must set up an administrative review process for:
  • Multifamily residential developments in areas zoned for multifamily housing or in commercial areas that allow multifamily uses.
  • Requests for mixed housing.
  • Some development processes (like final plats) must have clear deadlines and cannot be made more burdensome after a deadline.

• Design standards (for small projects)

  • For residential buildings with four or fewer units, local rules cannot require:
  • Minimum exterior finish materials
  • Minimum garage size
  • Roof pitch higher than 4:12
  • Specific building orientation or entrance requirements (except street-facing entrances in some cases)
  • Minimum number of windows or more than one aboveground floor
  • Historic districts are exempt from these limits.

• Homeowners associations (HOAs)

  • A municipality generally cannot condition a permit on creating an HOA or on the HOA’s rules.
  • Municipalities may regulate maintenance or insurance of common elements or allow utility easements to access public infrastructure.

• Mixed housing in greenfield development

  • Municipalities must allow mixed housing as a permitted use on at least 33% of land zoned for single-family housing.
  • When choosing locations for these districts, priority should be given to lots near transit, schools, parks, and commercial areas.
  • On greenfield lots, minimum lot sizes:
  • Cannot be larger than 1/8 of an acre.
  • Townhouses on greenfield lots or in mixed-housing zones cannot have minimum lot sizes larger than 1,500 square feet of habitable space per unit (the bill emphasizes space, not just lot size).
  • Bulk controls cannot be so restrictive that they prevent at least 1,500 square feet of habitable space per unit.

• Accessory dwelling units (ADUs)

  • At least one ADU must be allowed as a permitted use on any residential lot containing a single-family home, regardless of lot size.
  • ADUs must meet emergency access spacing and district setback minimums.
  • The ADU can stay on the same parcel as the primary home and may not be sold separately from the primary home unless allowed by the developer or local rules.

• Multifamily developments in commercial districts

  • Municipalities must allow multifamily developments as a permitted use in at least 33% of commercially zoned areas.
  • Ground-floor commercial space can be required, but it cannot be required for multifamily affordable housing.
  • No height limitations lower than the tallest building that is allowed in the same district; bulk and setback rules cannot be more restrictive than those for commercial buildings in the same district.

• Additional requirements and density rules

  • Cities must meet certain criteria (a mix of how land is zoned and how density is allowed) depending on city class (large, medium, small).
  • Potential incentives include:
  • Allowing mixed housing on a larger share of land, and/or reducing parking requirements to one space per unit in some cases.
  • Increasing floor area ratio or height by up to 25% for workforce housing, multifamily affordable housing, or senior housing.
  • Allowing at least eight units per lot in at least 15% of single-family-zoned land in mixed housing areas.
  • Eliminating all parking minimums in some circumstances.
  • Cities must publicly report compliance, including zoning maps and siting priorities.

• Infrastructure and legal coordination

  • Developments may need to meet local infrastructure standards to protect health and safety.
  • The bill does not authorize developments that are prohibited by state or federal law or floodplain/shoreland protections.
  • The density provisions in this bill prevail over conflicting provisions in existing state law in cases of higher residential density.

• Interim ordinances and density

  • Cities cannot use interim ordinances to delay or block the new requirements.
  • The bill emphasizes policies that can increase density, where appropriate.

Significant changes to existing law

• Expands local housing options and reduces barriers:

  • Adds strong emphasis on allowing ADUs and mixed housing across more areas.
  • Requires multifamily housing in more commercial districts.
  • Enables higher density and reduced parking requirements.

• Limits local design restrictions:

  • Prohibits certain design mandates (for small projects) that could restrict the type or size of housing.

• Streamlines approvals:

  • Creates an explicit administrative review pathway for MF and mixed-housing projects with timelines and predictable processes.

• Shifts control toward density and proximity factors:

  • Encourages siting near transit, schools, parks, and commercial areas.
  • Sets quantitative density incentives (e.g., higher floor area ratios, taller buildings) for specific affordable or workforce housing.

• Increases transparency:

  • Requires municipalities to publish compliance information and zoning maps.

• Preemption of conflicting local rules:

  • Density and certain housing provisions in this bill override conflicting parts of existing chapter 473 where applicable.

Short summary

The bill pushes local governments to permit more housing types (ADUs, mixed housing, multifamily in more places), simplifies and speeds up approvals, and reduces or removes certain design and parking barriers. It also introduces density incentives to encourage affordable and workforce housing, while requiring transparency about compliance and siting. These changes are aimed at expanding housing supply and choices, especially near transit and urban centers, but they limit some local zoning controls to achieve those goals.

Relevant Terms accessory dwelling unit; bulk control; greenfield lot; mixed housing; duplex; triplex; quadplex; townhouse; multifamily residential development; multifamily affordable housing development; residential unit; single-family home; townhome; administrative review; ground floor commercial; floor area ratio; parking minimums; density; transit; development agreement; final plat; emergency services access; setback; higher density; housing policy; zoning district; commercial district; ordinance; public information.