Project consisted of extending Boeing's existing 40-32 assembly building at the Everett site and designing a door system to allow 787's to exit the main assembly building to the north. The building extension was 12 feet long by 300 feet wide by 115 feet tall, with an 80 feet tall by 240 feet wide opening. Eight self-propelled door leaves, each 30 feet wide by 80 feet tall, were designed to open into door pockets in the side tower framing.
Due to the shortness of the extension, the new building framework was tied into the existing building for lateral support. The new framework was self-supporting for dead, live and snow loads, but incorporated friction dampers and framing features to be seismically compatible with the existing 40-32 building structure. Challenges included an accelerated design and construction schedule to support factory integration project, and coordination with other consultants on related internal and external modifications.
CP&A's scope included demolition of the existing exterior wall, foundation and door track design, door pocket towers, 240-ft span header truss, upper door guides, self-propelled door leaves with drives and controls, and construction support services. For the header truss the General Contractor initially planned to use conventional steel assembly using construction cranes for erection. This was expensive and slow to accomplish and entailed major disruption to existing parking and traffic. CP&A suggested remote pre-assembly and fully-assembled erection that utilized the new side towers as jacking towers. This saved several hundred thousand dollars, minimized traffic disruption, and cut several weeks off the construction schedule.