Before You Build in Sammamish, WA: Permit & Rule Checklist (2026)

Sammamish caps residential fences at 4 feet in front yards and 6 feet in side and rear yards, with a lower 3.5-foot limit inside the sight-distance triangle at corners. Fences up to 8 feet may be approved with a permit and a recorded neighbor agreement.

Standard fences within Sammamish's height limits (4 feet front, 6 feet side/rear) generally do not need a building permit, but a fence taller than 6 feet, or any fence reaching the 8-foot maximum by exception, requires a Type I Construction Permit and a recorded neighbor agreement.

Sammamish does not set a general shared-cost rule for boundary fences, but its code makes neighbor cooperation mandatory for tall fences: a fence over 6 feet (up to 8 feet) on a shared side or rear lot line requires a recorded agreement, including a maintenance agreement, with the adjoining owner.

In Sammamish, a fence on top of a rockery, retaining wall, or berm is limited so the fence portion does not exceed 6 feet measured from the top of the wall, and the combined fence-plus-wall height is capped (10 feet in lower-density residential zones). Separate engineering and permits apply to the wall itself.

Sammamish allows a wide range of fence materials including stone, brick, concrete block, wood, metal, mesh, rails, and composites. There is no general aesthetic material mandate for residential fences, but barbed wire, razor wire, and non-certified electric fences are barred in residential zones.

Building permits are required for most residential pool installations in Sammamish. The City has adopted the 2021 International Swimming Pool and Spa Code (ISPSC) at SMC 16.05.157 and the 2021 Washington State Residential Code at SMC 16.05.080. Permits are applied for online through MyBuildingPermit.com. Small prefabricated above-ground pools under 24 inches deep and 5,000 gallons are exempt.

Under the Sammamish Building and Property Maintenance Code (SMC Chapter 16.25), private swimming pools, hot tubs and spas containing water more than 36 inches deep must be completely surrounded by a fence or barrier at least 48 inches high, with openings too small to pass a 4-inch sphere and self-closing, self-latching gates. New-construction barriers must also meet the 2021 ISPSC.

Sammamish enforces statewide pool safety rules through the adopted 2021 ISPSC (SMC 16.05.157) and SMC Chapter 16.25. Requirements include perimeter barriers, self-latching gates, door/window alarms or powered safety covers for walls formed by the house, anti-entrapment suction outlets with dual drains, and required handholds and entry/exit means in pools.

Small prefabricated above-ground pools under 24 inches deep, holding 5,000 gallons or less and installed entirely above ground, are exempt from building permits in Sammamish. Larger above-ground pools need permits and must meet the adopted 2021 ISPSC barrier rules. Where the pool wall is the barrier, it must be 48 inches high and the ladder must be removable or lockable.

Hot tubs and spas in Sammamish fall under the adopted 2021 ISPSC (SMC 16.05.157) and SMC Chapter 16.25. A spa or hot tub holding water more than 36 inches deep needs a 48-inch barrier, but a spa or hot tub with an approved locking safety cover (ASTM F1346) is exempt from the fence requirement. Electrical and gas connections require permits.

Sammamish permits up to two ADUs on lots with a detached single-family home. A detached ADU may be up to 1,000 sq ft; an attached ADU up to 50% of the house or 1,000 sq ft, whichever is larger. No extra parking is required if the lot already has four or more spaces.

Converting a garage into living space in Sammamish generally creates an attached ADU, which the city allows. An attached ADU may be up to 50% of the home's size or 1,000 sq ft, whichever is larger. Permits are required, and any new parking demand is evaluated under the ADU parking rules.

Sammamish does not require a building permit for a storage shed that is no more than 200 sq ft and no more than 12 ft tall, on a site free of critical areas. Larger sheds need a permit, and all sheds must meet zone-based setbacks (front 10-20 ft, rear and side 5-10 ft).

Carports are treated as residential accessory structures in Sammamish. A simple storage structure of 200 sq ft or less and 12 ft or less may be permit-exempt, but most carports need a permit and must meet zone-based setbacks (front 10-20 ft, rear and side 5-10 ft) and height limits.

Sammamish has no separate tiny-home ordinance. A permanent tiny house on a foundation is treated as a detached ADU, capped at 1,000 sq ft, and the city allows up to two ADUs per single-family lot. Movable tiny houses on wheels are not recognized as permanent dwellings.

Recreational fires in pits, rings, or chimineas are allowed in Sammamish but limited to 3 feet by 3 feet by 2 feet and must be at least 25 feet from structures and combustibles. Only charcoal or seasoned natural wood may be burned, and fires are banned during burn bans.

Burning yard waste and land-clearing debris is prohibited in Sammamish, which lies within the Puget Sound Clean Air Agency's urbanized no-burn area. Only small recreational fires using charcoal or dried wood are allowed. Burn barrels and trash burning are always illegal.

In Sammamish, heavy pruning of a significant tree is regulated like removal. The tree standards (SDC 21.03.060) treat pruning that removes more than one-third of a tree's branches as equivalent to removal, requiring a tree removal permit. Tree topping is discouraged by the Urban Forest Management Program. Right-of-way street trees need a Right-of-Way permit.

Sammamish has strong tree-retention rules. Removing a 'significant tree' (coniferous 8 inches DBH or larger, deciduous 12 inches DBH or larger) requires a tree removal permit under SDC 21.03.060. Annual and 10-year removal limits scale with lot size. Removed significant trees must be replaced, and unlawful removal carries a civil penalty of $1,500 per inch of trunk diameter (SMC 23.100.010).

The City of Sammamish runs no water utility and imposes no mandatory citywide watering restrictions. Water comes from special-purpose districts — chiefly Sammamish Plateau Water. Their current guidance is voluntary conservation: water two or three times a week, before 10 a.m. or after 6 p.m. Mandatory limits would come from the water district or a state drought declaration.