New innovation in 'mass timber' means buildings could be built cheaper and lighter

[Pedestrian]

Non-North Americans often criticize the North American fondness and extensive use of wood construction. This is for them:

May 25, 2017, 11:54am PDT
Christine Kilpatrick

. . . A number of engineers, architects, developers and contractors are touting the potential of a building material called “mass timber,” prefabricated wood panels that can be cut to precise specifications and assembled onsite. The newest innovation in mass timber panels is cross-laminated timber, or CLT, where the wooden planks are oriented at right angles and glued together.

“CLT is like the rock star of mass timber,” said Dean Lewis, project manager at DCI Engineers. “You can use it for walls, roofs, anything. You can use it in seismic areas, the panels themselves are extremely strong. It’s comparable to concrete.”

. . . CLT panels are made of fast-growing trees that can be harvested sustainably. The panels can also be quickly assembled, saving time and money.

“You only need five or six crew members to lay a 4,000-square-foot floor plate in two to four hours,” Lewis said . . . .

“With mass timber, I could build a building that is one-fifth the weight of concrete and build it three times faster, and build it so it will sway back and forth. It will not crumble in an earthquake,” (wood products manufacturer Kris) Spickler said . . . .

Greater heights, however, prompt concerns about fire safety, Lewis said. Building codes impose an 85-foot cap for wood or timber construction. But mass timber burns differently than stick-frame construction, he said: Only the outside burns, forming a layer of charring that insulates the interior wood . . . .

“It has tremendous spanning capabilities so you don’t have to support it as often,” (architect Mark) Davis said. “You don’t need beams every four feet, more like eight to 10 feet.”

The use of large panels allow(s) the creation of a 20,000-square-foot space with an airy, natural feel. The panels themselves (wouldn't) need to be covered with plaster or decorative wood . . . .