Seattle City Wire

After several years of collaborating with seismologists, geologists, and geotechnical and structural engineers, the Seattle Department of Construction and Inspections (SDCI) is sharing its draft Unreinforced Masonry (URM) Technical Standard. This document is the first step in establishing minimum seismic standards for the earthquake retrofit of Seattle’s 1,100 vintage brick buildings which are prone to collapse in an earthquake due to lack of structural reinforcements. 

In 2021, an effort spearheaded by the Alliance for Safety, Affordability, and Preservation (ASAP!) and Councilmember Herbold resulted in the passing of Joint Resolution 32033. That resolution declared the intent of City Council and the Mayor to establish a mandatory retrofit program and directed SDCI to develop a retrofit standard. While a mandatory ordinance is still a few years away, this Technical Standard will serve as a voluntary option for URM owners wanting to retrofit their building. This Technical Standard will be used to develop a future mandatory retrofit ordinance.

The Technical Standard provides two pathways for a building owner to retrofit their building, neither of which will be a contributing factor to trigger a substantial alteration.

1. Comprehensive method: This method improves the life safety of the building and brings the structure into compliance with seismic retrofit performance standards consistent with the Seattle Existing Building Code.
2. Alternate method: This method provides a minimally acceptable level of safety from collapse by requiring the installation of wall anchors, wall bracing, and parapet bracing. A building must meet certain criteria to qualify for this method.

Building owners should consult a structural engineer to determine their preference for building performance in an earthquake and design their retrofit accordingly.

SDCI will be hosting two webinars explaining the draft URM Technical Standard and how it was updated from a previous 2012 version to account for an improved understanding of our seismic hazard and soil conditions. These webinars are open to the public:

• Thursday, June 8, 2:30 – 4:00 p.m.
  • Link to register: https://seattle.webex.com/weblink/register/r5f2699d19804742f6ad7da855d73ffeb
• Monday, June 12, 11:00 a.m. – 12:30 p.m.
  • Link to register: https://seattle.webex.com/weblink/register/r5607484aa8301be658261141154f52ec

Original source can be found here.