Seattle, WA Earthquake Safety: Unreinforced Masonry (2026)

Unreinforced masonry (URM) buildings are Seattle's most significant earthquake vulnerability. These buildings, constructed primarily of brick without steel reinforcement, are prone to catastrophic collapse during seismic events. SDCI has inventoried over 1,100 URM buildings in Seattle, concentrated in neighborhoods such as Pioneer Square, the International District, Capitol Hill, and Ballard. The city maintains a publicly accessible database tracking each URM building's address, use, and retrofit status. The 2021 Seattle Existing Building Code, adopted November 15, 2024, provides two pathways for URM retrofit recognition: the full code-based method and the Alternate Method. The Alternate Method is designed to reduce costs while still achieving meaningful life-safety improvements, focusing on securing walls to floors and roofs, bracing parapets, and strengthening connections. SDCI's URM Policy Committee has recommended a phased mandatory retrofit program with timelines based on building occupancy and use, prioritizing buildings with the highest risk to life safety. The city has applied for FEMA Hazard Mitigation Grant Program funding to support retrofits in underserved communities. A proposed transfer of development rights (TDR) program would allow URM building owners to sell unused development capacity to generate retrofit funding.