The Commercial Station forms a transfer point between the Expo and Millennium Lines. Its situation in the Grandview Cut presented large site issues during the construction phases. The existing Expo Line had to be kept running throughout the construction. There were access issues constructing in the bottom of the "cut" - which also required much site work to shore up the sides of the natural formation in order to protect the line from the potential effects of erosion.
A large steel truss bridge was erected to connect the upper Expo Line to the lower Millennium Line. This created a multi level station and much opportunity for overview of the structure and form of the finished station.
As with many of the stations, the structure uses a combination of Architecturally Exposed Structural Steel and glue laminated beams. The steel (and concrete) used for the columns presents a durable structure that is more resistant to traffic.
photos: George Third & Son, Terri Meyer Boake