Parallam parallel strand lumber (PSL) came on the scene at the Expo 86 in Vancouver, British Columbia, and quickly left a mark on the building industry, according to Carlos Guilherme, VP engineered lumber products for Weyerhaeuser.
"The invention of Parallam was one of those building material breakthroughs that happen maybe once or twice in a generation," Guilherme said. "Engineers and scientists invented a new product that took a great building material -- wood -- and made it even better."