Olympia, WA Building Safety: Fire Sprinkler Requirements (2026)

Section 16.32.140 rewrites IFC 903.2.8. For Group R fire areas, an automatic sprinkler system installed under Section 903.3 is required throughout the building, except as provided for Group R-3. Under 903.2.8.1, a fully automatic residential fire sprinkler system must be designed, installed, tested and maintained per NFPA 13D, RCW 18.160 and approval of the Fire Chief.

The City of Olympia lists the Group R3 structures that need it: new single family residential units of any size; new Accessory Dwelling Units with utilities served by a residential unit that has an existing sprinkler system; any change of use to a residential structure; any structure demolished and rebuilt for residential use; any structure adding greater than 50 percent of the existing square footage; any structure damaged by fire such that greater than 50 percent is being reconstructed or that is substantially damaged, as determined by the Building Official or the Fire Chief; and any modular, factory-built dwelling or mobile home placed on an established mobile home or recreational vehicle park.

The exceptions are detached carports and greenhouses; sheds and auxiliary structures under 200 square feet not used for human habitation; garage conversions to ADUs and ADUs with utilities served by an existing single family residence without a sprinkler system; temporary emergency housing structures permitted under Chapter 18.50 OMC; and replacement of a modular, factory-built or mobile home in similar kind, based on square footage, in a park prior to January 1, 2021.

Installation follows OMC 16.40.090: shop drawings and a plan check fee go to the City first, the fire protection systems permit must be obtained before work starts, systems are installed as prescribed in NFPA 13, 13D, 13R, 2010 Editions, and no Certificate of Occupancy is granted until acceptance tests are satisfactory. The fire chief or authorized representatives enforce under § 16.32.100.