Permit Requirements in Seattle, WA (2026)
4 verified permit requirements rules for Seattle, Washington, sourced directly from the municipal code and official government pages.
Verified from official government sources
Shed & Outbuilding Permits
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.
Shed Permit Requirements in Seattle
Some RestrictionsSDCI Sheds — Permits and Land Use Code (SMC Title 23, Chapter 23.44 Neighborhood Residential)
A shed is a small, single-story building used to store tools or other items. You don't need a permit to build a shed if it meets all of these criteria: The total area (or "footprint") of the shed's roof is 120 square feet or less. The shed is a single-story building. The shed sits on a simple concrete slab, pier blocks, or soil. The shed is not attached to a house or other building. The shed is...
Fence Permits
Most residential fences in Seattle do not require a building permit. Fences 8 feet or shorter without masonry or concrete above 6 feet are exempt. Fences in flood-prone areas, shoreline zones, or environmentally critical areas may need additional review.
Fence Permit Requirements in Seattle
Few RestrictionsSDCI Fences — Permit Requirements (Seattle Residential Code R105.2)
What Permits Do You Need? You don't need a permit if you're building a fence with a total height of 8 feet high or less that doesn't have masonry or concrete elements over 6 feet. You will need a construction permit if the fence will be located in a flood-prone area. If you're building a taller fence, you need a construction permit. Most fences require only a construction subject-to-field-inspe...
Deck & Patio Permits
Most decks in Seattle require a subject-to-field-inspection construction permit from SDCI. Patios and platforms under 18 inches above grade that are not over a basement do not need a permit. Decks over 36 inches above ground count toward lot coverage limits.
Deck and Patio Permit Requirements in Seattle
Some RestrictionsSDCI Decks — Permit Requirements (Seattle Residential Code R507.9.1.3, SBC 1015.2.1)
Decks — A single-family deck is an outdoor platform built above the ground; it may or may not be attached to a house. What Permits Do You Need? You need a permit to build a deck if it is: More than 18 inches above the ground; A roof deck (built on top of part of the building); In an environmentally critical area (ECA), for example landslide-prone or flood-prone areas. Most decks require only a ...
Renovation Permits
Seattle requires construction permits for most home renovations including structural changes, electrical work, plumbing, HVAC, and adding/removing walls. Minor cosmetic work like painting and replacing fixtures generally does not require permits.
Home Renovation Permit Requirements in Seattle
Some RestrictionsSDCI Construction Permit - Addition or Alteration (Tips 100/101/102)
Construction Permit - Addition or Alteration — You need a construction permit to remodel or add onto your building, whether it is a single-family house, multifamily building, or a commercial or industrial building. New structures that are accessory to an existing house, such as a detached shed or garage, are considered additions. An addition involves changes to the outside of the building, such...
Looking for King County county-wide rules?
County ordinances apply to unincorporated areas and may supplement Seattle city rules.
Permit Requirements in King County →