Seattle exempts one-story detached sheds from building permits if the projected roof area is under 120 square feet and the foundation is a slab on the ground. Larger sheds require a construction permit from SDCI. All sheds must comply with lot coverage and setback requirements.
Seattle's Department of Construction and Inspections (SDCI) requires building permits for most accessory structures, with specific exemptions for small sheds. A one-story detached accessory building (greenhouse, tool shed, storage shed) is exempt from a building permit if the projected roof area is less than 120 square feet and the foundation is only a slab on the ground. Sheds cannot exceed 12 feet in height. Even exempt sheds must comply with zoning setbacks and lot coverage limits. In neighborhood residential zones (NR1, NR2, NR3), the combined footprint of all structures (house, garage, shed, elevated decks) cannot exceed 35% of the lot on lots 5,000 sq ft or larger, or 1,000 sq ft plus 15% of lot area on smaller lots. Sheds with electrical, plumbing, or mechanical systems require appropriate trade permits regardless of size. Sheds in environmentally critical areas may require additional review. Prefabricated sheds still must meet all zoning requirements.
Building without a required permit: penalty fees plus retroactive permit costs. Non-compliant structures may be required to be removed.
Seattle, WA
Seattle's Land Use Code allows residential lawn ornaments, statuary, and yard art without permits provided structures do not exceed accessory-structure heigh...
Seattle, WA
Seattle does not regulate residential inflatable holiday decorations by size or type. Standard Noise Ordinance (SMC 25.08) limits apply to blower-motor noise...
Seattle, WA
Seattle has no ordinance restricting when residents may put up or take down holiday lights. The general Noise Ordinance SMC 25.08 applies to any amplified ou...
Seattle, WA
Built-in outdoor kitchens in Seattle require building permits from SDCI when they include new electrical, plumbing, gas piping, or a structural roof under Se...
Seattle, WA
Backyard wood and pellet smokers in Seattle are allowed at single-family homes but are subject to Puget Sound Clean Air Agency (PSCAA) Regulation I, Section ...
Seattle, WA
Seattle Fire Code Section 308.1.4 prohibits open-flame cooking devices and LP-gas containers larger than 1 lb on combustible balconies of multi-family buildi...
See how Seattle's shed & outbuilding permits rules stack up against other locations.
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