Tacoma’s land-use code sets a 1,000-square-foot habitable-area cap but delegates many height and setback questions to the applicable district and housing type. A citywide ADU height number would miss that structure.
Local standards
The selected local standards are summarized in the Tacoma Municipal Code §13.06.080(A) — Accessory Dwelling Units. Attached and detached ADUs follow the relevant housing-type standards for height and location. In View Sensitive Districts, a Backyard Building containing one or two ADUs follows the primary structure’s height. The area measure excludes garages and other nonliving space.
Confirm the applicable rule
A specific conversion provision covers a permitted or legally nonconforming accessory structure in an R or UR district that existed by February 1, 2025. It may be converted despite existing setback, location, height, or other development nonconformity if current Building Code and required pedestrian-access conditions are met. Confirm the current code, housing type, legal status, and structure date. Zoning measurements do not by themselves establish fire separation, building-code compliance, utility capacity, or permit approval. For shared measurement methods, see the setback and separation guide and floor-area guide.
