Design Green Design Katerra Is Shaking Up the Construction Industry, Literally and Figuratively By Lloyd Alter Design Editor University of Toronto Lloyd Alter is Design Editor for Treehugger and teaches Sustainable Design at Ryerson University in Toronto. our editorial process Facebook Facebook Twitter Twitter Lloyd Alter Updated October 11, 2018 ©. Katerra CLT structure on the shake table Share Twitter Pinterest Email Design Tiny Homes Architecture Interior Design Green Design Urban Design We’ve been watching Katerra, the ambitious construction startup that calls itself a technology startup. Their pitch: Katerra is bringing fresh minds and tools to the world of architecture and construction. We are applying systems approaches to remove unnecessary time and costs from building development, design, and construction. With the latest technology at our fingertips, efficiency no longer has to come at the expense of quality or sustainability. One of the technologies that they are using is Cross-Laminated Timber (CLT). TreeHugger has noted how it is sustainable, being made from wood, a renewable resource (if it is harvested sustainably). It’s also really efficient; the big slabs of wood are cut to size in the factory and assemble on site quickly, quietly and neatly. In fact the very first tall timber tower, designed by Waugh Thistleton a decade ago, was assembled in nine weeks by four workers. Now Katerra demonstrates that CLT buildings can be remarkably earthquake resistant. On July 27 they tested their CLT design on the big shake table at the UC San Diego. We have noted before that wood is one of the “most suitable material for earthquake resistant construction due to its light weight and shear strength across the grains.” But much depends on how the wood panels are fastened together, because at some point, something’s gotta give. © Katerra/ connection plate Katerra has designed a new kind of seismic shear wall system, with an odd looking connector, full of long slots instead of being a solid plate connector. There is also a rocking mechanism at the base of each panel, which lets the building absorb energy and flex horizontally. They tell us the results: Under medium intensity the system experienced no damageUnder large and extreme intensity, damage occurred, but only at the connection devicesCollectively, the CLT performed as well as steel or concrete. However, in the event of an earthquake, Katerra’s wall system allows the damaged connection devices on the building to be pulled out and replace, often within just hours, rather than scrapping the whole structure – something not possible with steel or concrete. © Katerra details They then replaced the connection devices and tested the structure again, proving that buildings built this way could actually be fixed. This is a very big deal when anticipating very big quake; billions of dollars are still being spent reinforcing concrete buildings after lessons were learned from the 1994 Northridge earthquake. Architects and builders have to think about repairability as well as survivability. We do it all. Katerra has been pretty much invisible, in what they call "stealth mode" until recently, but now claims to have a billion dollar valuation, over 500 employees and more than $550 million in booked jobs. According to the portfolio on their site, they have exactly one project complete, a renovation in Las Vegas, but lots under construction and in development. Services they offer include architecture and engineering, Interior design, construction management and general contracting. They also sell products, from structural components to mass timber to plumbing hardware. They claim: "We do it all. Faster and more efficiently than ever before." I really want them to succeed. But do worry because they say "every building shouldn't be a one-off prototype" when unfortunately, every building pretty much is; that is the nature of the business because every building is on a different piece of land, in a different town or city with its own zoning bylaws. They say they do it faster, but have no control over the approval process, the NIMBYs, the parking requirements that put four floors of concrete construction underneath their efficient and fast buildings. Perhaps they have reinvented that too. Having worked as an architect and builder in the prefab world, I have been skeptical about whether Katerra can disrupt the industry (see Can you really build a building like an iPhone?). But as we see from this testing, they are certainly shaking things up.