WA HB1840

Counties planning under the Growth Management Act may authorize at least one middle housing unit on parcels zoned for single-family residences in designated urban growth areas and limited areas of more intensive rural development

Maximum density in limited areas of more intensive rural development is capped at 4 residential units per lot, and middle housing in these areas must be served by sewer service

Middle housing cannot be subject to more restrictive standards than detached single-family residences, though objective regulations like setbacks, lot coverage, stormwater, and tree canopy requirements may still apply

County ordinances and development regulations implementing this middle housing authorization are exempt from administrative or judicial appeals under the State Environmental Policy Act (SEPA)

The Growth Management Hearings Board is prohibited from hearing petitions alleging noncompliance based on a county's implementation of these middle housing requirements within an urban growth area