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 | Jun 13, 2017 | News
Timber construction is opening a new market that has been keeping lumber and milling machinery busy at a growing number of wood products companies, including Montreal’s Nordic Structures, Sauter Timber in Rockwood, Tennessee, SmartLam, in Columbia Falls, Montana, and D.R. Johnson, in Portland, Oregon.
Oregon-based D.R. Johnson Wood Innovations, a subsidiary of D.R. Johnson, specializes in the manufacture of cross-laminated timber, or CLT, and glue-laminated beams from Douglas fir and Alaskan yellow cedar. D.R. Johnson Wood was the first U.S. company to receive APA/ANSI certification to manufacture structural CLT panels – and CEO Valerie Johnson plans to help grow the U.S. market.
D.R. Johnson has received the first U.S. certification to manufacture cross-laminated timbers (CLT) under a new standard approved last year by the American National Standards Institute. D.R. Johnson is one of only three North American companies certified by the Engineered Wood Association to construct CLT for use in buildings.
Johnson’s company employs 125 at a traditional sawmill and laminating plant, which was recently expanded by 13,000 square feet for increased CLT production. They’re currently fielding calls from hopeful builders, and manufacturing samples to be tested for fire safety and structural quality. One recent new wood construction project is a 14-story wooden apartment tower being built in Portland, Oregon.
From Woodworking Network: https://www.woodworkingnetwork.com/wood/pricing-supply/timber-construction-has-lumber-milling-machinery-rolling
by Web Editor | Jun 7, 2017 | News
Officials in Oregon have approved construction permits for the first all-wood high-rise building in the nation. Construction on the 12-story building, called Framework, will break ground this fall in Portland’s trendy and rapidly growing Pearl District and is expected to be completed by the following winter.
The decision by state and local authorities to allow construction comes after months of painstaking testing of the emerging technologies that will be used to build it, including a product called cross-laminated timber, or CLT.
To make CLT, lumber manufacturers align 2-by-4 boards in perpendicular layers and then glue them together like a giant sandwich before sliding the resulting panels into a massive press for drying. The resulting panels are stronger than traditional wood because of the cross-hatched layers; CLT can withstand horizontal and vertical pressures similar to those from a significant earthquake with minimal damage. They also are lighter and easier to work with than regular timber, resulting in lower cost and less waste.
For this project, scientists at Portland State University and Oregon State University subjected large panels of CLT to hundreds of thousands of pounds of pressure and experimented with different methods for joining them together. The project materials also underwent extensive fire safety testing and met fire codes.
State officials hope the building will stir greater interest in high-rise construction using mass timber and help revitalize the state’s lagging logging industry. Logging, once a major source of revenue in Oregon, has dropped sharply in the past few decades because of greater environmental protections for salmon and the spotted owl. The loss of the industry has devastated some of the state’s rural communities.
From The Register-Guard: https://registerguard.com/rg/news/local/35651365-75/portland-approves-permit-for-nations-first-all-wood-high-rise.html.csp
by Web Editor | Apr 5, 2017 | News
The U.S. Forest Service is working to build markets for innovative forest products. One of these products, cross-laminated timber, also known as CLT, offers an opportunity for raising tall buildings with wood, opening up a completely new market for wood products.
And there’s tremendous opportunity to increase the market share for wood-based construction. Because of its high strength, CLT is an advantageous alternative to traditional building materials such as concrete, masonry, and steel. Because CLT panels resist compression, they are well-suited for building multistory structures, especially mid-rise buildings. Made from layers of dried lumber boards, stacked in alternating direction at 90-degree angles, glued and pressed to form solid panels, CLT has exceptional strength and stability and can be used as walls, roofs, and floors.
Additionally, CLT is highly resilient to fire, earthquakes, and even explosions. In fact in a recent series of live blast tests, CLT passed with flying colors. An examination of the results showed that the CLT structures suffered less degradation than expected and might outlast concrete and steel.
In terms of fire, CLT is like using a large log to start a campfire—it doesn’t ignite easily. And when it does burn, a char layer forms on the outside, protecting the inside and allowing the wood panel to maintain its structural integrity during fire scenarios.
Researchers have conducted extensive seismic testing on CLT and found that the panels perform exceptionally well in multi-story applications. When a seven-story CLT building was tested on the world’s largest shake table in Japan, it survived 14 consecutive earthquake simulations with almost no damage.
From the USDA: https://www.usda.gov/media/blog/2017/04/04/build-better-stronger-faster-clt
by Web Editor | Feb 20, 2017 | News
The long wait for Australian-made cross laminated timber (CLT) is nearly over. Xlam Australia will open its first CLT manufacturing plant in Wodonga and be producing panels for construction by the close of 2017.
The company shared its plans to build a factory in the Albury Wodonga region with Architecture & Design last year, but only now do we know that it is actually going to happen. Fairfax is reporting that the plant has the backing of local, state and federal government and will be complete by April.
The facility will produce 60,000m3 of CLT each year and at capacity production will produce enough to build a project the size of Forte Melbourne – Australia’s largest timber apartment building – each week. It will be produced from local pine, increasing demand for the plantation industry and shortening delivery time and distance.
Currently, CLT is being purchased overseas from companies like Stora Enso, Meyer Timber and Novatop. Australia’s Lendlease has opened a prefabrication plant in Sydney that manufactures CLT framework but it doesn’t create the actual CLT.
Xlam has a number of Australian projects currently underway, including a massive CLT house designed by Fitzpatrick + Partners director James Fitzpatrick.
From Architecture & Design: https://www.architectureanddesign.com.au/news/australian-made-clt-from-local-plantation-forests
