Pierce County, WA Accessory Structures: Shed & Carport Rules (2026)

B lets a structure typically accessory to a residence, such as a garage, carport, greenhouse, or storage building, sit on a lot without any principal use present, capped at 576 total square feet, and it cannot be used as living space. B says they are not treated as a principal use and are not limited to the 576-square-foot maximum when no principal use is on site. E are exempt from that 2,000-square-foot limit. a: a detached, single-story accessory structure (other than an ADU) may occupy up to 25 percent of an interior yard or 50 percent of a rear yard, and must still keep a minimum 3-foot setback from the property line in either location.

A there is no cap on the number of accessory uses on a lot as long as each meets applicable development regulations and remains accessory to a lawfully established residence. D through F round out the rule: every accessory use must stay customarily incidental and subordinate to the principal use (D), must be discontinued or removed once the principal use ends (E), and if a use's classification is in dispute, the Planning and Public Works Director makes the final call based on compatibility with the surrounding land use pattern (F).