Concerning residential development in commercial and mixed-use zones.

Removed a separate rule (subsection c) regarding the 20 percent commercial area limit, merging it into the main text to simplify the language.

Clarified the condition for allowing more than 20 percent commercial space by explicitly stating it applies to the 'total area within its jurisdiction' rather than an area outside station areas.

Added a new definition for 'total area,' specifying that it includes commercial and mixed-use zones but excludes station areas.

Changed the header for subsection (9) from 'For the purpose of this section' to 'For the purposes of this section' to accommodate the new list of definitions.

Added a new definition for 'publicly subsidized affordable housing' to ensure clarity on tax exemptions.

Removed redundant line numbers and formatting artifacts from the bill text.

The bill number was changed from Z-0561.2 to S-4447.1 to reflect its status as a substitute bill.

The prefile and first reading dates were updated from January 7/12 to January 29, 2026, and the sponsor designation was updated to reflect the Housing Committee.

New subsections allow cities to require mixed-use or ground-floor commercial space in station areas and up to 20% of areas outside station areas, unless the project is publicly subsidized affordable housing.

A new requirement mandates that cities allowing mixed-use or ground-floor commercial requirements must permit a height increase of at least 10 feet in at least 30% of the area.

Exemptions for requiring commercial space were expanded to include buildings listed on historic registers, business improvement areas, and commercial areas designated as main streets by the state.

The exemption for shoreline environments was narrowed from 'waterfront lots' to areas 'adjacent to' shoreline environments where multifamily development is prohibited.

The exemption for critical areas was expanded to include critical area buffers in addition to critical areas themselves.

A new definition clarifies that 'publicly subsidized affordable housing' refers to housing exempt from property taxes under RCW 84.36.560.

Expanded applicability to include non-rural counties in addition to cities, broadening the number of jurisdictions subject to the zoning reforms.

Relaxed restrictions on requiring ground-floor commercial space by allowing up to 20% of areas outside transit stations to have such requirements, and added a new provision allowing more than 20% if a height incentive is provided.

Added a new requirement for cities and counties to conduct an empirical study and adopt specific zoning incentives or reductions to balance housing needs with ground-floor commercial use.

Added a new exemption allowing mixed-use requirements in tax increment financing areas.

Removed the specific exemption for areas designated as main street areas from the list of places where the residential mandate does not apply.

Extended the timeline for updating growth and development assumptions until the next comprehensive plan update after January 1, 2031.