King County Code Title 21A controls house bulk through floor-area, lot-coverage, and height limits rather than a dedicated mansionization ordinance, with stricter standards in rural and Vashon Island zones to preserve neighborhood character.
Unlike Los Angeles, King County does not have a dedicated mansionization ordinance, but the Zoning Code (KCC Title 21A) controls oversize single-family homes through several tools: maximum lot coverage, floor-area-ratio limits in some overlays, structure height caps, and setback requirements. Rural Area, Vashon-Maury Island, and Snoqualmie Valley zoning use stricter floor-area and lot-coverage standards to protect character and critical areas under KCC Title 24. Cities inside King County apply their own bulk standards, with Seattle's neighborhood overlays and Bellevue's R-zones being notable examples. Local Services Permitting reviews bulk compliance during single-family permit review.
Building beyond the lot coverage, height, or floor-area limits in KCC Title 21A is a zoning violation, triggering stop-work orders, redesign requirements, and possible removal of nonconforming construction.
Auburn, WA
Auburn applies WAC 173-60 EDNA limits through ACC 8.28. Residential: 55 dBA day, 45 dBA night. Industrial receiving: 60 dBA day, 50 dBA night. Measured at th...
Auburn, WA
Industrial sources into residential zones are capped at 60 dBA day and 50 dBA night under WAC 173-60 via ACC 8.28. The Boeing Auburn plant and Valley warehou...
Auburn, WA
Federal law preempts local aircraft noise. Auburn Municipal Airport follows FAA Part 150 and Sea-Tac overflights are under FAA and Port of Seattle. ACC 8.28 ...
Auburn, WA
Outdoor concerts and festivals must meet ACC 8.28 limits and often need a special event permit. Downtown Auburn and Les Gove Park events follow a written noi...
Auburn, WA
Auburn restricts RV, trailer, and boat parking on public streets to 72 hours and sets additional limits on driveway and front-yard storage of recreational ve...
Auburn, WA
EV charging in Auburn follows the Washington State Energy Code, which requires EV-ready capacity in new multifamily and commercial parking and protects publi...
See how Auburn's anti-mansionization rules stack up against other locations.
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