Seattle committee advances interim upzoning plan amid sharp debate over trees, ECAs and affordability

Seattle’s Select Committee on the Comprehensive Plan on April 16 reviewed Council Bill 120969, interim legislation the mayor proposed to implement state middle‑housing laws including House Bill 1110. Committee staff briefed members on density limits, floor‑area rules, development standards and optional affordability bonuses; public commenters urged stronger protections for trees, steep slopes and environmentally critical areas. The committee set a schedule for amendments, a public hearing and committee and full‑council votes this spring.

The bill would implement state requirements to allow middle housing across most residential zones and includes specific local rules: a maximum structure height of 32 feet (plus pitched roof allowances), standardized setbacks, and an increased maximum lot coverage of 50% in neighborhood residential zones. The draft also ties floor‑area ratio (FAR) to the number of units on a lot, exempts certain middle‑housing types from parking within a half mile of a major transit stop, and establishes an optional affordability bonus: developers could build up to six units on qualifying lots if at least two units are kept affordable (80% AMI for ownership; 60% AMI for rentals) for 50 years.

Why it matters: the city must adopt interim rules to meet the state deadline for HB 1110 implementation, while advocates and neighborhood residents warn that the interim bill’s changes to…