Snohomish County, WA Building Setbacks & Zoning: Structure Height Limits (2026)

032, the same bulk matrices that set lot coverage and setbacks. Height limits vary sharply by zone: R-20,000 caps out at 25 feet, R-12,500 and WFB at 30 feet, R-9,600 and R-8,400 at 30 feet, R-7,200 at 35 feet for buildings up to 30 feet with a different side/rear setback triggering above that line, RB and CB at 35 feet, GC at 45 feet, IP and HI at 65 feet, and the Urban Center (UC) zone up to 90 feet. A table note caps commercial forestry structures at 65 feet and another caps non-residential structures generally at 45 feet.

Subsection (2) exempts specific features from the height cap entirely, including tanks and bunkers, religious facility spires, water towers, flagpoles, and radio/TV antenna masts, as long as they sit back at least 50 feet from any adjoining lot line; schools and educational institutions can also exceed the zone limit up to 55 feet with a conditional use permit and a 50-foot perimeter setback for the taller portion. Subsection (3) governs how height itself is measured: building height is the vertical distance from the average final grade to the highest point of the roof surface, using the tallest point for flat or minimally-pitched roofs, the deck line for a mansard roof, and the pitch's midpoint for gable, hip, gambrel, vaulted, shed, or A-frame roofs.

Subsection (4) lets an applicant measure height section-by-section for a fully partitioned attached single-family structure that follows sloped terrain, and subsection (5) bars using more than five feet of fill to artificially raise the average final grade within 50 feet of an adjoining dwelling.