Issaquah planning panel advances middle‑housing and ADU draft rules; council sees tentative May 19 adoption

Issaquah’s Planning, Development & Environment (PDE) Committee reviewed draft regulations to comply with Washington's recent middle‑housing laws and to update accessory dwelling unit (ADU) standards, committee chair Councilmember Hall reported April 7.

The PDE recommendations are intended to implement state requirements referenced in recent legislation (House Bill 1110 and House Bill 1337) and to revise the city’s Title 18 zoning code. "The first item on our agenda was middle housing draft regulations, so this is to come into compliance with the new state requirements," Hall said.

The nut graf: Committee members recommended changes that would increase allowed residential density and expand middle‑housing types in single‑family zones; the package is scheduled for tentative council adoption at the May 19 meeting and could change development rights across many neighborhoods.

Highlights Hall summarized included allowing up to two dwelling units per lot generally, permitting up to four units per lot within a quarter‑mile of a major transit stop or if one unit meets the committee’s affordable‑unit criteria, and requiring the city to allow a roster of middle‑housing building types (duplex, triplex, four‑plex, townhomes, cottage housing, and a sixth building type noted in committee materials). For ADUs, the draft would allow up to two ADUs per lot in any configuration, remove the previous owner‑occupancy requirement, and restate a 1,000‑square‑foot threshold for internal ADUs.

Hall said the Planning Policy Commission and other advisory bodies had reviewed drafts and offered input; the city plans additional outreach before final action. Councilmembers thanked planning staff by name for the work and noted the May 19 tentative adoption date for the package.

No final code changes were adopted tonight; the committee’s recommendations will return to the full council for consideration on the May 19 agenda.