Haddon Hall Seismic Retrofit Study and Design

Haddon Hall Seismic Retrofit Study and Design

Seattle, WA

Built in 1910, Haddon Hall is a 7-story, 29,000 SF unreinforced masonry (URM) affordable housing apartment building in the heart of downtown Seattle. It has 6 floors above grade over 1 basement level. SSF performed a Tier 1 building evaluation per ASCE 41-13, and designed the seismic upgrades using the Special Procedure for Unreinforced Masonry Buildings (URM) per Seattle Existing Building Code.

The structural design includes adding steel braced frames, extending the mid-building shear wall through the bottom 3 stories, securing the exterior URM walls to the deck diaphragms, and laying new plywood sheathing throughout the building. Interior architectural improvements include upgrades to the windows, roofing, and mechanical/electrical systems.

The owner decided to not move forward with the construction of this project.




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