Authorities having jurisdiction in Oregon and Portland have granted a building permit for the 12-story Framework, which is on deck to become the tallest, pure mass-timber structure in the Americas and the tallest mass-timber building in the U.S. The University of British Columbia’s 174-ft Brock Commons dormitory, set to open in September, is the world’s tallest timber building, but it has structural-concrete cores. Framework’s design also calls for an exposed timber structure. Walsh Construction plans to start work in the fall for a late 2018 completion. “The real achievement is that, through performance-based design, we’ve been able to [meet] requirements specific to high-rise buildings,” says Thomas F. Robinson, founding principal of Framework’s Lever Architecture. “The two-hour fire rating without sprinklers was the major hurdle.”