Nearly every aspect of Portland International Airport is getting a redo as the $2-billion PDX Next project redevelops or expands two concourses, adds parking, updates operations and features a core terminal redevelopment. But the megaproject’s pinnacle piece is an innovative, nine-acre, seismically isolated curved timber roof that uses locally sourced materials. …The undulating timber roof highlights what Granato hopes will become a focal point of the updated PDX. ZGF architect Gene Sandoval says what makes it all work are the “roots” that not only support the roof but also open and modernize the space inside the terminal.  “You don’t get a roof like that without touching every single part of that building,” says Sharron van der Meulen, ZGF architect. “We had to deal with functional and operational aspects of the future.” The roof uses nearly 400 glulam beams—more than 250 of them are 80 ft long—paired with 40,000 lattice pieces atop 34 Y columns.