... a breathtaking, mass-timber structure that looks like a cross between an ark, a bird’s nest, and an enormous, cozy pine cone, Asikainen shows me an array of wood composites of the sort that might fill Klein’s buildings. There is cross-laminated timber (CLT)1, which looks like inch-thick strips of heartwood arranged like a Jenga set to produce a block that is pretty much the definition of the word solid. Or glu-lam, used to make structural beams that are like extremely strong plywood, and LVL—laminated veneer lumber—which makes excellent heavy beams and had formed the skeleton of the apartment building.

To a designer like Klein, those blocks don’t just use less carbon than concrete or steel, they lend themselves better to modern architecture. “We’re basically computer scientists now,” he says, and wood is simply a better, more plastic material for the design programs he uses to simulate building layouts based on his customers’ needs, which are always changing.

Klein envisions a future urbanization boom like the one he saw in China in the early 2010s, when he worked at breakneck speed designing high-rises as cities like Shanghai filled in to accommodate the millions moving there. Mass timber, he says, is much easier to customize and prefabricate than concrete or steel: it allows designers to send plans directly to the factory to be built to spec in a practice he calls “file to factory.” That translates to faster construction, lower costs for labor, and less disruption for existing cities.

“Right now, every building is prototype,” he says—built to spec, never repeated.

....

• 1. But for all the hype around mass timber, only a few U.S. firms east of the Mississippi are making it. Which means, for now, that if you want to build a CLT building, you have to order the materials from Europe, from factories like Binderholz in the stunning Zillertal Valley in the Austrian Alps.