Mountain Line’s new Downtown Connection Center is scheduled to open in May. The $29.5 million facility will be a hub for Mountain Line riders, drivers, dispatchers, operations and administrative staff. …It’s all in a two-story, 20,938-square-foot building designed to meet Coconino County’s sustainable building standards. The environmentally-friendly design by HDR Inc. feature cross-laminated timber. It’s only the second building in Arizona to use mass-timber rather than the more common building framework of concrete and steel. …Timberlab, based in Portland, Oregon, provided the mass-timber materials for the transit center using Douglas fir, according to Sam Dicke, the company’s manager of client development. Some advantages of mass-timber construction include the need for fewer workers to assemble the posts and beams, and it can reduce the construction schedule by about 20%, he said.