Building Setbacks & Zoning in King County, WA (2026)

3 county-level rules, plus city-specific rules for 8 cities in King County, Washington.

Verified from official government sources

Note: These county rules apply to unincorporated areas of King County. If you live within an incorporated city, that city's own rules apply — see the city list below.

Setback Rules

King County sets setbacks under KCC 21A.12. Urban R-4 through R-8 zones require 10-foot front, 5-foot side, and 10-foot rear. Rural Area zones require 30-foot front setbacks.

King County Building Setback Rules

Some Restrictions

Full ordinance details →Official source ↗

Structure Height Limits

King County caps most residential structures at 35 feet under KCC 21A.12. Accessory buildings are limited to 25 feet or the primary dwelling height, whichever is less.

King County Structure Height Limits

Some Restrictions

Full ordinance details →Official source ↗

Lot Coverage Limits

King County regulates lot coverage under KCC 21A.12 and 21A.24. Urban zones allow 35-55 percent building coverage. Rural zones limit impervious surface to 8 percent or 15,000 sq ft.