Construction of the 6,000 square-foot addition to the BC Cancer Agency’s Vancouver Centre, where a powerful new research tool called a cyclotron has been installed, was completed in the summer of 2010. Viaduct Sheet Metal carried out the mechanical sheet metal on the project using a design-build concept. Nearly half of the mechanical sheet metal portion of the project was made of galvanized metal, and the other half, made of stainless steel, had to be welded. The building runs continuously at full makeup air and exhaust air. A more specific challenge was the installation of a 60-inch wide, 80-feet high welded stack made to withstand ten inches of static part pressure.