by Web Editor | Aug 21, 2017 | News
Ever since the 10-story Home Insurance Building in Chicago was called the first “skyscraper” in 1885, architects have been striving to create ever-taller buildings. Ten stories quickly became 20, 20 became 50, and on and on. In 2009 the Burj Khalifa in Dubai became the world’s tallest building, with its 154 floors towering above ground level.
So why is the mayor of Portland, Oregon, calling a modest 12-story tower set for completion there next year “a true technological and entrepreneurial achievement?” It’s not the affordable housing the building affords, nor its dozens of bike racks or even the roof farm that has Ted Wheeler gushing. It’s that the Framework apartment building will be made almost entirely of wood.
Once completed, Framework will be America’s tallest wooden building and its first “plyscraper” — a high-rise building built with panels made of cross-laminated timber (CLT). These modular sheets are made from cheap, sustainable softwood that are glued or pinned together in layers — a bit like super-strong, super-thick plywood.
While the raw material might vary in quality, CLT (also known as mass timber) is engineered to be stronger than concrete. CLT panels resist earthquakes and even fire, charring instead of catching alight like the lumber in typical homes.
Plyscrapers can be bolted together in days, and they require a fraction of the labor use to erect traditional steel-and-concrete high-rises. “You don’t need an experienced master carpenter to do this,” says Casey Malmquist, founder of Columbia Falls, Montana-based SmartLam, one of only two CLT manufacturers in the U.S. “It literally goes together like Legos.”
From NBC News: https://www.nbcnews.com/mach/tech/eco-friendly-plyscrapers-are-rise-here-s-why-ncna793346
by Web Editor | Aug 4, 2017 | News
If Yugon Kim realizes his dream, the new office building or housing complex going up in your city may be made out of large hardwood panels called cross laminated timber (CLT). The technology behind CLT has been used for decades in Europe, and it is just beginning to take root in the United States with softwood CLT leading the way. Kim’s Boston-based, architectural design firm IKD just won a $250,000 grant from the Forest Service for designing, developing and constructing the first hardwood CLT demonstration project in the United States.
The aim is to take low-value hardwoods and turn them into a high-value CLT construction project as a proof of concept. Kim explained, “Over 50% of every hardwood log in the region goes to low-value materials like pallets and cants. Our idea is to utilize this material and to upcycle it.”
Kim along with his design partner Tomomi Itakura have created an outdoor CLT construction project that is titled the Conversation Plinth and will be integrated as circular discs that provide a platform for viewing a sculpture at the Cleo Rogers Memorial Library.
Kim suggested, “The ultimate goal is to construct buildings in the United States using hardwood CLT. Our research hopes to lead toward hardwood mass timbers being used for U.S construction projects.”
The Conversation Plinth was designed for Exhibit Columbus, the annual celebration of architecture, art, design and community in Columbus, Indiana. IKD’s design was selected to win an inaugural J. Irwin and Xenia S. Miller Prize as part of a national competition.
From Pallet Enterprise: https://palletenterprise.com/view_article/4927/Hardwood-CLT
by Web Editor | Jul 21, 2017 | News
Silicon Valley design-build firm Katerra is using a technology-driven and full-services approach to creating prefabricated structures at a large scale. Based in Menlo Park, California, Katerra was started in 2015 by Michael Marks, Jim Davidson and Fritz H Wolff. Combined, the three men have decades of experience in the technology, manufacturing, real estate and private equity industries. In 2007, Marks served as the interim CEO at Tesla.
The design-build startup – which describes itself as a technology company – has about 60 architects on staff, along with 10 interior designers. The team is led by architect Craig Curtis, who formerly was a partner at The Miller Hull Partnership, a prominent Seattle firm.
Katerra’s overarching mission is to streamline the design and construction process while still providing good architecture. “Our goal is to remove unnecessary time and costs from the building process while also providing world-class design,” said the firm, which is one of the investors in Architizer’s online marketplace for architectural products.
Katerra believes it stands apart from other design-build firms because of its focus on utilizing technology and modular components to create large-scale multifamily, commercial and institutional projects. It also handles all steps of the building process, including site development, schematic design, fabrication of parts and onsite construction. “Through curating our own high-quality supply chain we can provide a fully coordinated design, much like what you would expect when buying a car,” the firm said. “By working within one fully integrated service model, clients no longer need to depend on multiple partners and vendors.”
The firm generally uses wood frame construction, with several upcoming projects featuring cross-laminated timber (CLT). “Katerra is aggressively pursuing CLT, with plans to help North America start using the material on scale with Europe,” the company stated.
From Dezeen: https://www.dezeen.com/2017/07/19/katerra-combines-technology-modular-construction-large-scale-prefabricated-buildings/
by Web Editor | Jul 19, 2017 | News
The International Code Council Ad-hoc Committee on Tall Wood Buildings provided five fire scenarios that were tested in each of the two one-bedroom apartments constructed using mass timber in a multi-story apartment building. The test scenarios included various arrangements of exposed and unexposed cross-laminated timber (CLT) with open doors between living and sleeping areas while the effectiveness of automatic sprinkler systems was simultaneously evaluated.
Test 1: a mass timber structure fully protected with gypsum wall board was subjected to a large furnishings and contents fire. The test was terminated after three hours without significant charring on the protected wood surfaces of the structure.
Test 2: approximately 30 percent of the CLT ceiling area in the living room and bedroom were left exposed. The test was terminated after four hours, providing additional time to determine if there would be any significant fire contribution from the exposed CLT. Notably, once the furnishings and contents had been consumed by the fire, the exposed CLT essentially self-extinguished due to the formation of char that protected the underlying wood.
Test 3: parallel CLT walls were left exposed, one in the living room and one in the bedroom. Similar to Test 2, once the apartment furnishings and contents had been consumed by the fire, during which a protective surface of char formed on the CLT, the mass timber surfaces essentially self-extinguished.
Test 4 and 5: examined the effects of sprinkler protection. For both tests, all mass timber surfaces in the living room and bedroom were left exposed. Test 4 demonstrated that under normal operating conditions, a single sprinkler easily contained the fire. For Test 5, the fire was allowed to grow in the compartment for 23 minutes before water was supplied to the sprinklers which quickly controlled the fire.
From Woodworking Network: https://www.woodworkingnetwork.com/architectural-products/cross-laminated-timber-fire-testing-sees-promising-results?ss=news,news,woodworking_industry_news,news,almanac_market_data,news,canadian_news
by Web Editor | Jul 17, 2017 | News
A two-story cross-laminated timber (CLT) structure is being subjected to the forces produced by a 1994 6.7 Northridge earthquake. The engineered simulation is expected to reveal ways in which tall wood buildings could survive damaging earthquakes.
Workers constructed a 22-foot tall wood test structure on UC San Diego’s shake table, a device for shaking structural models or building components with a wide range of simulated ground motions, like earthquakes.
Led by the Colorado School of Mines (CSM), the new test will examine the viability of constructing quake-resistant CLT buildings that could be as tall as 20 stories high.
“We are working to minimize the amount of time buildings are out of service after large earthquakes,” CSM engineer Shiling Pei said in a statement. “We are also focused on cutting the costs required to repair them.”
Cross-laminated timber advocates say it can be used to construct buildings of equal strength and fire-resistance as those made of steel and concrete. It has also fueled the passions of architects and environmentalists, who believe it to be a much greener method for housing the world’s growing population.
From Woodworking Network: https://www.woodworkingnetwork.com/two-story-cross-laminated-timber-simulated-67-earthquake?ss=news,news,woodworking_industry_news,news,almanac_market_data,news,canadian_news
