Shed Permit requirements across Washington
By Mario Bailey Last verified 2026-06-17
Requirements and size thresholds for shed permits vary by locality. The table below compares what each Washington county or city requires. Always confirm with the local office before starting.
| Locality | Permit required? | Typical threshold |
|---|---|---|
| Bellevue | Conditional | detached storage sheds playhouses or gazebos with a floor area of 200 square feet or less do not require a building permit; structures over 200 square feet require a permit |
| King County | Conditional | storage sheds 200 sq ft or less as accessory to a residential house do not require a building permit in unincorporated King County; sheds over 200 sq ft require a permit |
| Seattle | Conditional | one-story detached storage sheds with a roof footprint of 120 square feet or less on a slab foundation and not in an environmentally critical area do not require a permit |
| Tacoma | Conditional | one-story detached accessory structures with a floor area of 200 square feet or less do not require a building permit; structures over 200 square feet require a permit |