The $1.2-billion contract to build a separate addition to Seattle’s Washington State Convention Center has required crews to work under an active downtown street, build components while hanging over sidewalks and the freeway, create fresh approaches to bringing natural light into the building and employ a billboarding construction method to keep everything on schedule.
The addition, being constructed by a joint venture of Clark Construction and Lease Crutcher Lewis, is going up one block from the current convention center— with a portion of the structure cantilevered over Interstate 5. Work began in summer of 2018, and the project team is targeting a summer 2022 completion.