Accessory Structures in Tacoma, WA (2026)
4 verified accessory structures rules for Tacoma, Washington, sourced directly from the municipal code and official government pages.
Verified from official government sources
ADU Rules
Tacoma allows two accessory dwelling units per residential lot, each capped at 1,000 square feet of habitable area, with no parking required.
Tacoma ADU Size and Number Standards
Some RestrictionsTacoma Municipal Code § 13.06.080A
Number. Two ADUs shall be allowed per residential lot as a subordinate use in conjunction with any new or existing residential development in the City of Tacoma. … The habitable area of ADUs, excluding any garage area and other non-living areas, shall be limited to a maximum of 1,000 square feet. … No off-street parking is required for ADUs.
Shed & Carport Rules
Tacoma caps accessory buildings like sheds at 1,000 square feet, or 15% of lot area, and requires they sit behind the main house and out of side-yard setbacks.
Tacoma Accessory Building Size & Setback Limits
Some RestrictionsTacoma Municipal Code § 13.06.020H
Accessory buildings permitted per Section 13.06.020, such as garages, sheds... are subject to the following location and development standards: The total square footage of all accessory building footprints shall be no more than 85 percent of the square footage of the main building footprint and no more than 15 percent of the square footage of the lot, not to exceed 1,000 square feet... Detached...
Garage Conversions
Tacoma allows homeowners to convert an existing garage or other accessory structure into a legal dwelling unit without meeting current setback, height or location standards, as long as it meets Building Code.
Tacoma Garage-to-Living-Space Conversion
Some RestrictionsTacoma Municipal Code § 13.06.080A.4.i
Conversion of existing accessory structures to residential use. Permitted or legally nonconforming accessory structures, existing as of February 1, 2025, in a UR or an R district may be converted to a dwelling unit regardless of conformance to setback, location, maximum height, or other development regulation. The building must be brought into compliance with current Building Code requirements ...
Tiny Homes
Tacoma normally requires manufactured homes built as two sections at least 12 by 36 feet each, but structures meeting IRC Appendix Q tiny-home standards skip that minimum-size rule.
Tacoma Tiny Home Sizing Exception
Some RestrictionsTacoma Municipal Code § 2.02.620.C
All manufactured homes shall be comprised of at least two fully-enclosed parallel sections, each of not less than 12 feet wide by 36 feet long unless the structure complies with the requirements of IRC Appendix Q – Tiny Homes, as amended by the State Building Code. D. Manufactured homes shall be set upon a permanent foundation, as defined by the Housing and Urban Development (“HUD”) handbook...
Looking for Pierce County county-wide rules?
County ordinances apply to unincorporated areas and may supplement Tacoma city rules.
Accessory Structures in Pierce County →