Posts tagged with "Timber Construction":

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Shigeru Ban’s timber tower in Vancouver on track to begin construction

The Shigeru Ban-designed Terrace House in Vancouver, set to become the tallest hybrid timber tower in North America once it’s finished, has received its official Building Permit and can begin construction. Vancouver-based PortLiving is developing the 19-story, 232-foot condo high-rise, which will contain only 20 luxury units and features a mixture of glass, concrete, and wood for the building’s terraced 12-story podium. The triangular seven-story extension at the building’s top will drop the concrete façade and expose the underlying structural timber, which is partially the reason for the delay in permitting. The approval of an “Alternative Solution” permit by Vancouver’s Chief Building Official’s Office means that the exposed timber complies with the city’s structural, fire and seismic-related regulations, and has been proven as safe as a conventionally-constructed tower of the same height. While no timber buildings of this height have been approved for construction before in either the U.S. or Canada, Canadian Architect notes that the 18-story Brock Commons, a mass timber student residence at the University of British Columbia, was allowed to rise after it covered all of its exposed timber with fire-rated gypsum. Earlier this month, Shigeru Ban Architects Americas released a first look at renderings of Terrace House’s interiors. The homes inside of the gable-shaped topper will receive full-floor views of the surrounding city and mountains, and will keep the wood floor slabs fully exposed. Ban will also be designing all of the fixtures, handles, pulls and millwork for each of the 20 units. Terrace House is located in Vancouver’s waterfront Coal Harbor, and Ban has stated that he specifically sought to reference the neighboring Evergreen Building, a landmarked tower designed by the late architect Arthur Erickson, through the use of layered terraces, triangular forms and natural materials. Viewed from the street, the cascading balconies of the Evergreen Building, seem to become a natural extension of Ban’s Terrace House.
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New timber research finds exciting potential in steel and concrete composites

With mass timber projects on the rise around the United State, Skidmore, Owings & Merrill (SOM) and Oregon State University (OSU) have partnered to produce two new reports on how timber buildings can overcome their technical limitations by integrating steel and concrete. The new composite systems being proposed would allow timber construction to rise higher than before, with longer floor spans. The OSU Testing Report, released earlier this month, looked into the possibility of combining cross-laminated timber (CLT) floor systems with a concrete topper, to improve the strength of the flooring as well as lengthen its span. To accurately represent real-world conditions, the SOM team first drew up plans for a “typical” 11-story residential building and indicated where the wood columns would normally be. With the floor span determined, the CLT flooring was stress tested for load, bending, cracking and shearing, before and after the application of a concrete slab. A 2.25-inch thick concrete layer was applied over a 6.75-inch thick CLT floor for the experiment. After testing smaller, individual sections, an eight-foot-by-36-foot full-sized mockup was created and subjected to load testing, only failing after engineers applied eight times the normal service load, or around 82,000 pounds of pressure. One complicating factor is that CLT can be charred for a higher fire rating at the expense of its strength, and any real-world application of CLT would need to be thicker than in testing conditions. Still, the results are a promising first step to increasing floor spans in timber buildings as well as improving their acoustic properties. The second report was produced in conjunction with the American Institute of Steel Construction (AISC) and examined how steel framing can best be integrated with timber floor systems. Because steel framing can span much greater distances than timber with smaller columns, and because CLT is lighter than concrete, a building that uses both should get the best of both worlds. In SOM’s modeling, this combination model was equally as strong as a steel and concrete building while offering window bays of the same size as a typical residential building. Ideally, high-rise timber construction of the future would combine both of these techniques, as the concrete slab topper adds extra seismic protection. With timber construction offering the potential for more sustainable, durable and quickly assembled towers, hybrid research could be a stepping stone towards bringing mass timber construction into the mainstream. All of SOM’s timber research reports can be found here.
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The lumber industry responds to the rise of mass timber

This is an article from our special November timber issue. North America’s lumber industry helped define what it means to build in the modern era. With the invention of the light balloon–frame, lumber became an indispensable resource to the quickly expanding United States in the 19th century. Over the past 150 years, the process and politics of wood have shaped a highly efficient industry that still provides the vast majority of the U.S.’s house-building material. With new technology, wood is pushing into new territories, and the lumber industry is bracing to respond to these demands. The process of harvesting lumber has dramatically changed since the industry began to standardize and organize in the late 1800s. No longer will you find any teams of two-person saws felling ancient trees or a Paul Bunyan-esque worker swinging an axe. Most of the industry became highly mechanized in the 1970s with the invention of the harvester. Harvesters, invented in Scandinavia, are tree cutting, moving, and trimming vehicles that have drastically reduced the danger and time involved in lumber work. Crawling through the forest, harvesters reach out with an articulated arm, grab a tree by the base with its nimble claw, then cut, trim, and lift the bare log onto the back of a transport vehicle. This can all be done by one operator, and during the process the tree is measured and catalogued. This entire process has added efficiency and sustainability to an industry that carefully balances a fine line of production and conservation. In North America and Europe, long gone are the days of clear-cutting forests and destroying an entire region’s ecology. While clear-cutting “slash and burn” operations still happen in parts of South America and Africa, they are due to the expanding, unregulated livestock and agriculture industries, not the timber industry. The careful regulation and scientific study of the lumber industry in the United States and Canada have led to a net increase of 1 percent of forested land over the last 50 years. That means the forests of North America are stable, with a slight increase, even as roughly 45.5 billion board feet of lumber are harvested in the United States in a single year. This is thanks to precise tree selection, sometimes using satellite imagery and GPS, and aggressive tree-growing programs. While much of the harvesting techniques have been streamlined, the politics behind harvesting have been anything but. Most notably, the Canada-U.S. softwood lumber dispute is considered one of the greatest points of trade tension between the two countries. The disagreement is directly linked to how and where lumber is coming from. In the United States, most lumber comes from the property of 11 million private U.S. landowners. In Canada, most land dedicated to lumber harvesting is owned by the government. In the interest of maintaining a healthy economy, Canadian provincial governments subsidize the industry, effectively keeping the price of lumber low and stable. This is in direct conflict with the private-market-driven prices U.S. companies charge. Over the past 40 years, a number of lawsuits and agreements have been filed and disputed between the two countries over Canada’s subsidies and the movement of lumber over the border. While this dispute is currently at an uneasy truce, the potential of new wood technologies is promising to drive the demand for lumber to new heights. Roughly 80 percent of all lumber harvested in the world is softwood. Despite its name, softwood, as opposed to hardwood, is not defined by its softness, but rather by the species of tree it comes from. Softwoods are generally conifers, such as pines, firs, and cedars, while hardwoods come from broad-leaved trees, such as oaks, maples, and hickories. Softwoods have long been used for light-frame construction, while hardwoods have been traditionally used for heavy timber construction, as well as fine woodworking due to its often-fine grain. Although the lumber industry is confident it can handle an increase in demand, there are factors that will need to be addressed. As of yet, there are few standards for producing heavy timber, CLT in particular, and legal definitions are also lacking. The industry is developing so fast that local fire codes have not been established for the material. At the same time, architects, lumber producers, and manufacturers across North America are looking to Canada and Europe for a way forward, while innovating in their own right.
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Experimental Swiss apartment wants to bring timber into the 21st century

The Wood Materials Science department at ETH Zurich in Switzerland is pioneering new ways of utilizing timber and wood construction by imbuing the traditional material with extraordinary properties using its new Vision Wood apartment prototype. The multidisciplinary team—guided by department head Tanja Zimmermann and wood materials science professor Ingo Burget, and joined by a slew of industry partners—developed the prototype apartment in an effort to find new uses for the continent’s abundant, but mostly underutilized, beech lumber. Beech lumber is a hard and versatile wood with superb structural capabilities, but it is also prone to sun damage, rot, and warping. To combat these maladies, the team developed a slew of experimental applications of beech wood building components that have been waterproofed, magnetized, and mineralized in order to broaden their residential applications. The team, for example, subjected the wood to laccase-catalyzed reactions in order to derive a wood fiber–based insulation that eliminates the need for synthetic binding agents. The fully sustainable biopolymers—made from lignin compounds and modified starch naturally found in wood—were molded into tongue-and-groove-shaped insulation blocks that can be packed into building cavities, providing a nontoxic insulation material. Another innovation came in the form of an exterior-cladding coating application developed from gelatinous nanofibrillated cellulose. The varnish improves UV protection, waterproofing, and resistance to microorganism infestations and cracks for exterior wood treatments. The apartment interiors—which will be occupied by a pair of doctoral students—are rife with new applications, including antimicrobial wood surfaces treated with an enzymatic method developed by university researchers that utilizes a bacteriostatic iodine coating to kill bacteria. The application has been used on door handles in kitchens and bathrooms in the unit in an effort to improve indoor hygiene. The apartment features hydrophobic wood sinks in the bathroom that have been treated in situ with polymerizing agents that not only repel water from their surfaces but are also designed to give the appearance of untreated wood. The researchers inserted iron oxide nanoparticles into wooden blocks to develop a magnetized task board that utilizes the natural structure of wood to create a material that can be selectively magnetized as well. On top of that, the team developed a fire-resistant mineralized wood panel system that can be used for doors and other interior applications in lieu of toxic flame-retardants. This panel system can be entirely sourced and fabricated in Switzerland and features reduced dimensions relative to traditional lumber construction due to the wood’s structural capabilities. In all, the test apartment points a way forward for wood construction that relies on abundant and local wood sources, while also pursuing sustainable and nontoxic material applications.
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Cross-laminated timber could lead a mid-rise revolution

This is an article from our special November timber issue. Engineers specializing in cross-laminated timber (CLT) see its future less in boutique prototype towers, requiring case-by-case demonstrations for approval, than in a meat-and-potatoes mid-rise market. While, according to Colorado State University's John van de Lindt, “some of those pioneering early CLT buildings are really almost like a partial R&D project in disguise,” he and colleagues predict that the field's maturation depends on the incorporation of research-driven CLT standards into building codes. “If you're going to just do a two-story residential home, you have a perfect design code pathway to do it,” said Shiling Pei of the Colorado School of Mines, chief investigator on a National Science Foundation (NSF)-supported study of seismic design methods. “But if you want to go taller, especially [if] you want to go above 85 feet— that is currently IBC [International Building Code] for Type IV, heavy timber—then you have to do something else...a lot of testing to try to convince the local building-code officials.” He views CLT beyond about 20 stories skeptically, on economic grounds: “In my projects, I say it's tall wood; it's not high-rise wood.” Pei cites the 2011 CLT Handbook by Canadian nonprofit FPInnovations as a pivotal document, republished in a 2013 U.S. edition with input from the American Wood Council (AWC), Forest Products Laboratory, WoodWorks, and APA: The Engineered Wood Association (formerly the American Plywood Association). In 2011, APA and the American National Standards Institute developed a performance-based standard, PRG 320, updating it in 2012 and 2017; it offers detailed specifications on CLT products' composition, dimensions, shear strength, stiffness, and other properties. The AWC's National Design Specifications for Wood Construction and the IBC include basic CLT sections in their 2015 editions. Since seismic risks in Europe (Italy excepted) are milder, the transfer of CLT technology to Canada and the U.S., particularly for larger scales and open plans, requires standards addressing lateral forces. The next hurdle is for the American Society of Civil Engineers' influential code book, ASCE 7: Minimum Design Loads for Buildings and Other Structures to address CLT, particularly its response-modification coefficient or R factor (not to be confused with R values for thermal resistance) in its seismic design provisions. “To make [CLT] economically competitive,” van de Lindt said, “it really needs to have these seismic performance coefficients (essentially an R factor) in the code, so that people don't have to get special permission every time they want to use it,” incurring engineers' reviewing costs. Results of van de Lindt's R-factor studies are expected next year, and the code-revision cycle takes about five years; if a proposal based on the findings passes review by Building Seismic Safety Council committees and a public-comment period, it should enter the 2022 edition of ASCE 7, then IBC. “With CLT, everything rotates like a rigid body under seismic stresses," van de Lindt said. "Panels do not deform enough to dissipate energy and suck load right into them.... For a steel special moment frame that's detailed for seismic, it can be an R of 8, [which has] a lot of ductility.” Yet adding concrete or steel lateral systems, as in Brock Commons (Acton Ostry Architects, Vancouver, page 12) and Carbon12 (PATH Architecture, Portland), respectively, requires multiple trades on-site and squanders CLT's construction speed. Advanced “disruptive technologies” common in Japan (base or inter-story isolation using sliders, rockers, or damping devices) require special review. Very tall wood, 20 stories and above, he believes, calls for performance-based modeling rather than prescriptive tables and “will always require review, at least in our lifetime.” Andre Barbosa of Oregon State University's School of Civil and Construction Engineering and Tallwood Design Institute concurred, noting that CLT projects above about ten stories are often hybrids with concrete cores or steel for lateral resistance. “You get the best out of both materials. You have the CLT that's lighter; [its] strength-to-weight ratio is very, very good. You get the concrete that allows you to go to longer spans, but also it creates that natural barrier for smoke and essentially for fire across floors.” Current methods of addressing timber's susceptibility to moisture and insects are generally adequate, he says, adding that long-term deflection (creep) in CLT buildings tall enough for large loads needs further study. Supported by the NSF's Natural Hazards Engineering Research Infrastructure Tall Wood program, Pei and colleagues recently built a two-story prototype for testing on the world's largest shake table at the University of California San Diego. Simulating 14 quakes of varying severity up through a "maximum credible earthquake," a once in 2,500-years event, “the building essentially received no damage, and we don't need to repair anything,” Pei reported, noting that CLT rocking walls actually outperformed their concrete and steel counterparts in resilience. His next studies will test a ten-story building under combined seismic stress and fire; the experiment has earned the inevitable nickname “shake and bake.” Flammability is “a concern very often expressed, but an easy one to dismiss,” said Lech Muszynski, associate professor of wood science and engineering at Oregon State University's College of Forestry. Studies support the counterintuitive idea that charring produces an insulating layer that actually slows pyrolysis, making it advance predictably and sparing enough wood to pass two-hour fire-resistance tests. “I've done some testing on unprotected CLT assemblies here in the states, large-scale floor and wall assemblies; there is a large library of similar tests being done in Europe in the past,” Muszynski reported, crediting Ario Ceccotti of the Istituto per la Valorizzazione del Legno e delle Specie Arboree (Trees and Timber Institute) for similar research in Italy and Japan. These tests have largely involved exposed CLT, though in practice the material is commonly encapsulated in gypsum board, adding another hour or so to its fire-resistance rating. Two commercial CLT manufacturers in the U.S., Muszynski noted, Oregon's D.R. Johnson (which he advises) and Montana's SmartLam, have their products fire-certified. Steel components within joints, Muszynski added, are more vulnerable than the wood. He uses a photo from the 1906 San Francisco fire to illustrate “the difference between flammable and fire-safe”: A severely burnt wooden beam shows charring and exposed nails, indicating deep fire penetration, but remains rigid, while two heat-weakened steel beams flop across the wooden member, resembling soggy pasta. Adhesives also require attention: Some bonded timber products use melamine urea-formaldehyde resins, which harden under heat, but the more common adhesive is polyurethane, which softens if the char reaches bond lines. Moisture can be more hazardous when worksite protections are lacking: Muszynski recalls an Italian project where financial delays left a site idle for several months, exposing CLT to rain—and underscoring the importance of using contractors familiar with the material.
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Shigeru Ban unveils latest designs for world’s tallest hybrid timber tower in Vancouver

Vancouver-based developer PortLiving has released the latest plans for the world’s tallest hybrid timber structure, designed by Japanese architect and 2014 Pritzker Prize awardee Shigeru Ban. Nicknamed the Terrace House, the project is located in Vancouver’s Coal Harbor neighborhood and pays tribute to its neighboring landmark-listed Evergreen Building, which was designed by late architect Arthur Erickson. The building, Ban’s first work in Canada and his tallest residential project to date, will house only 20 luxury apartments. Similar architectural cues of triangular shapes, natural materials, and green terraces create continuity between the Terrace House and Erickson’s building, according to the developers. “Shigeru Ban has tremendous respect for Arthur Erickson’s work. It was the opportunity to design a building next to one of Erickson’s masterpieces that initially drew him to this innovative project,” said Dean Maltz, managing partner at Shigeru Ban Architects Americas, in a press release. Cornelia Oberlander, the original landscape architect who worked on the Evergreen Building, and Hermann Blumer, an internationally renowned wood structural engineer, will be brought in to work with Ban. The wood, glass, and concrete building highlights Vancouver’s commitment to sustainable design and advanced timber construction, according to the developers. “We have brought together the best of the best—a team of true experts in creative collaboration, working together for the first time ever on a single project,” said Macario Reyes, founder and CEO of PortLiving, in a press release. “The result is truly a once-in-a-lifetime project setting new standards in design and construction.” Its exact height and dates of construction are unknown. Further project details will be released in coming months.
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U.S. to tax Canadian lumber—what could this mean for the construction industry?

The Unites States has picked a fight with one of its most peaceful trading partners, this time over a popular construction material. Yesterday the U.S. announced it will impose duties on imported Canadian softwood lumber. Canada, predictably, is not happy with the move. The U.S. Commerce Department said it will put in place "preliminary anti-subsidy duties" of around 20 percent, a move that will impact $5.66 billion in imports, Reuters reported. The decision comes as the U.S., Canada, and Mexico gear up to renegotiate North American Free Trade Agreement (NAFTA) later this summer. The U.S. said that Canada's West Fraser Mills would pay 24.12 percent, the highest duty rate, while J.D. Irving Ltd would pay the lowest (3.02 percent). Aside from a few other major producers, all Canadian timber companies will pay a 19.88 percent duty. This is only the latest point of contention in a decades-long dispute between the two countries over lumber. The U.S. government claims that Canadian timber producers, who harvest the wood on government land, have an unfair trade advantage over American timber producers, who typically get their wood from privately-owned property. In a statement, Canadian Natural Resources Minister Jim Carr and Foreign Minister Chrystia Freeland characterized the Commerce Department's claims as "baseless and unfounded." Canada said it will make moves to protect its lumber in court. All told, the duties would add up to about $1 billion annually, but could cause construction costs in the U.S. to rise. Wood yew like to learn more? Construction Dive has insight into what the move will mean for the AEC industry. The New York Times reports that a study by the National Association of Home Builders estimates that a tariff of 15 percent could raise new home prices by around 4 percent, while Bloomberg News gives greater context to the history of the hard-headed history of the softwood lumber dispute.
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Not your grandfather’s two-by-fours: A new exhibition showcases modern wood construction

Here we are in the year 2016, getting ready to ride in robot cars and eat meat grown in labs, but a skyscraper built out of wood still seems outlandish. Why? Wood is one of the world’s sturdiest and most versatile building materials. It has a single raw ingredient that doesn’t require intensive energy to produce: trees. The Horyuji temple precinct in Japan has wood structures that have been standing since about 700 AD. The onion-domed wooden churches on Russia’s Kizhi Island date to the early 18th century.

Today we have an innate distrust of tall wood buildings, a sense that they’ll roar into flame at the first spark. This distrust is, in part, a legacy of terrible 19th-century conflagrations like the Chicago Fire of 1871 and the Boston Fire of 1872. Those disasters and others led to the adoption of fire codes that prohibited wood structures above a certain height, saving lives in the process.

But it’s the 21st century, and a new exhibition at the National Building Museum in Washington challenges us to let go of our fear and embrace the future. The structural wood products that have recently entered the market are not your grandfather’s two-by-fours. Engineered timber beams have been proven in tests to be just as fireproof as steel, and arguably more so, since their cores as less likely to melt in a fire. They are also surprisingly strong.

In 2009, a nine-story apartment block in London was completed with an all-wood structure—load-bearing walls, floor slabs, elevator cores. Building with modern timber calls for a front-loaded process, which begins with sustainable forest management and expert milling (in close collaboration with the architect), and ends with a relatively quick assembly of prefabricated components. In other words, it changes how materials are sourced and how buildings are built. An overused cliché seems warranted here: Mass timber (the catch-all term for a host of different products) could disrupt the design and construction industries.

On display through May 21, 2017, Timber City occupies a single long room and part of the adjacent hallway on the second floor of Washington’s cavernous National Building Museum. Happily, wood is both the message and the medium in the exhibition design, by Yugon Kim and Tomomi Itakura of the Boston-based firm IKD. Information is presented on tall wooden boards propped against the walls. Large wood lozenges, stacked like pennies, hold the models. It’s a tactile and even olfactory show: Visitors can run a hand down a curved glu-lam beam, count the layers in a sandwich of cross-laminated timber (CLT), and compare laminated veneer to laminated strand lumber. Groups of tree stumps at either end of the room let you sit down for a moment to sniff the air (with so much wood, the room smells great).

Among the projects featured is a carousel pavilion in Stamford, Connecticut, that is just shy of completion, and a charter school in New Haven that opened a few months ago, both by Gray Organschi Architecture. The model of the carousel pavilion shows the undulations of precisely milled CLT in a cupola with three skylights, supported by a glu-lam rim beam. The UMass Design Building by Leers Weinzapfel Associates, now under construction in Amherst, Massachusetts, also makes extensive use of timber, including in its zipper-trussed atrium.

Those structures don’t exactly pierce the sky (the Design Building is four stories). But Framework, a project by Lever Architecture, will rise to 12 stories after it breaks ground next year in Portland, which will make it the tallest timber structure in the United States so far. Framework and another wood tower design by SHoP Architects, 475 West 18th (planned for a site on the High Line), won a prize from the U.S. Department of Agriculture, which is promoting tall timber—another sign this is not a passing fad.

For a small show, Timber City packs in a lot of information, and at times I wished it had more space to breathe. The Timber Over Time mural on one of the short walls is based on a clever conceit: It presents the history of wood construction through concentric tree rings. But as elsewhere, the text is small and dense. A board explaining the “forest-to-frame” life cycle is compelling—it really does seem to be a virtuous circle, with trees harvested at their carbon-storing peak, milled with little waste, and replaced by new growth—but I missed a more vivid sense of how trees become beams and boards. Too bad there wasn’t room to show footage from inside a factory or a time-lapse video of one of the buildings going up. (There is, however, a neat case of different wood byproducts that explains their uses.)

The exhibit is sponsored in part by the lumber industry, and it feels a bit like a sales pitch. But perhaps that’s necessary. The concrete and steel industries are huge; building codes are entrenched and slow to change (many of the early mass-timber buildings have gotten special code exemptions). Still an upstart, the timber camp may have to shout to make itself heard. Timber City proves that we all should be listening.

Timber City National Building Museum, Washington, D.C., through May 21, 2017

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Shigeru Ban lines up his first project in Canada: A hybrid timber tower with luxury apartments

Renowned Tokyo-based architect Shigeru Ban has joined forces with Vancouver-based developers PortLiving to design a hybrid timber tower filled with luxury condos in the Coal Harbor district of Vancouver. The scheme will take up one of the last plots still available an area already home to many high-end apartments. Ban, who won the Pritzker Prize in 2014, is known for his humanitarian architecture work as well as his use of sustainable materials and construction methods. The development in Vancouver will be known as the Terrace House and the building is due to follow in the footsteps of the architect's previous work. While this project will be Ban's tallest residential project and his first in Canada, the Terrace House will—according to press release from PortLiving—also be the world's tallest hybrid timber structure when complete. However, its exact height and dates for the project have yet been released. Using locally-sourced timber from BC Wood, the development hopes to achieve a minimal carbon foot-print while also setting a "new standard for luxury urban development, sustainability, and engineering innovation." “We are honoured to be working with Shigeru Ban and his team to bring a visionary design and new landmark to the City of Vancouver,” said Macario (Tobi) Reyes, founder and CEO of PortLiving in a press release. “We are extremely excited by Shigeru Ban’s decision to bring his craft to the Pacific Northwest, where we expect he will be embraced for his environmentally-sustainable approach, creative integration of outdoor living, and his leadership in innovation.” “Shigeru Ban Architects welcomes this chance to design our first building in Canada. It is an opportunity to embrace the natural beauty of the surroundings and to capture inspiring views,” said Dean Maltz, Partner at Shigeru Ban Architects USA. Further details of the project are due to be released later in the year. Stay tuned.
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Leers Weinzapfel Associates designs timber multidisciplinary design building for UMass Amherst

The University of Massachusetts (UMass) Amherst, about 100 miles west of Boston, will get a new multidisciplinary addition this fall. Boston-based Leers Weinzapfel Associates designed the UMass Design Building, set to open November 2016 in time for winter classes. It will unite the architecture, landscape architecture, regional planning, and building technology departments into one facility. The building is currently under construction. See our slideshow above and images below for exclusive construction photos (we've included a few renderings, too). When the project opens, it will be one of the largest mass timber structures in the United States. The building's interior will feature Cross Laminated Timber (CLT), an engineered wood known for its durability and lightness. Projects can use CLT to replace materials with higher embodied energy such as steel, concrete, and masonry. While it has been popular in Europe and Canada for some time, CLT is gaining traction in the United States, mostly on the west coast (one notable project is the Bullitt Center in Seattle). The 87,000 square foot Design Building will also rely on a glue-laminated wood frame, a wood composite floor, and a copper anodized aluminum building envelope. The facility will bring together over 500 students and 50 faculty across the four departments into a space that is transparent, open, and light-filled. The design features a lowered atrium with a zipper truss, an upper courtyard, and offices and classrooms rising in a coil, explained Andrea Leers, principal and co-founder of Leers Weinzapfel Associates. A major goal of the design was to help facilitate greater interaction between student and faculty. The firm put studios and offices on each floor, said Tom Chung, principal at Leers Weinzapfel. Yet there is also an element of independence, as studios on each level are at one end, while offices are at the other. The studios will be medium-sized, able to fit up to 5 sections. “UMass did not want a lecture hall,” Leers said. Instead, the ground floor—which has no predefined programming—includes stairs that double as seating for presentations and a flat floor for absorbing activities and other events. Also planned is a cafe, exhibit space, and libraries. The Design Building site is a sloped area on the southern part of the UMass campus between Stockbridge Way and Kevin Roche’s 1975 Haigis Mall. “It is a challenging site,” said Leers. The building will rise to four stories on one end and three stories on the uphill. The landscape design by Stephen Stimson Associates relies on a bioswale for water filtration. Leers Weinzapfel stressed the close connections between the exterior and interior, with the concept of building-as-landscape and landscape-as-building. In separate conversations with both Leers Weinzapfel architects and UMass building technology specialists, both emphasized the educational component of the Design Building—how the building itself would serve as a living instructional example. “We wanted this building from the early stages to be a teaching tool for advanced timber construction,” said Peggi Clouston, associate professor of building and construction technology at UMass Amherst. “The project uses CNC milled wood,” said Alex Schreyer, building construction and technology program director at UMass Amherst. “There are extremely tight tolerances. It’s innovative with these spans of 25, 26 feet.” But there are challenges to building in timber in the U.S. “The forests are in a state of decline. They are not properly managed, and weed species [smaller species] are choking out larger ones," said Clouston. These weed species are easy fuel for forest fires. The use of mass timber reflects the university’s roots in agriculture—the university was founded under the President Abraham Lincoln-signed 1862 Morrill Land-Grant Colleges Act. The university was first called the Massachusetts Agricultural College. “It was a public process,” said Josiah Stevenson, principal at Leers Weinzapfel of the design. The total cost of the project is $52 million, with $36 million going toward construction. When it came to obtaining funding, the UMass's efforts were partially an “activist intervention,” Leers explained. UMass faculty went to the state legislature for funding, and spoke with former Massachusetts Congressman John Olver. He was taken with timber, said Clouston. Currently down the hill from the Design Building site is Wood on the Plaza, a white ash timber bridge shell installation at the Fine Arts Center Plaza. The architecture department will be moving out of its home in a Brutalist Kevin Roche building. The university will reuse the current architecture and building technology spaces, while razing the landscape department building, originally built as a dorm. You can find more Design Building information, construction photos and time-lapse videos online. The construction manager for the project is Suffolk Construction.
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Architects in Vienna plan to build this skyscraper out of wood

Last year, AN's Midwest Editor Chris Bentley reported on the advances being made in wood construction and how we were on the verge of seeing tall timber towers sprout up around the world. The AEC community has been talking about building high-rise structures with wood for years, but there obviously hasn't been a major revolution with the building type just yet—the tallest modern wood building doesn't even top 100 feet. Well, that record is about to be shattered by a new tower in Vienna that could usher in a new era of high-rise development. The Guardian is reporting that a 276-foot-tall wood tower, known as the HoHo project, will start to rise in the Austrian capital next year. The designer of the project, Rüdiger Lainer and Partner, says the building will be made of 76 percent wood, saving 2,800 tons of carbon when compared to a similar concrete structure. Obviously, the creation of a wood building, especially a tall one, has people worrying about the elephant in the room: Fire. Since the building would be unprecedented, the Vienna fire service is reportedly working very closely with the architects to make sure everything is up to code and then some. “They have to carry out special tests on the correct combination of concrete and wood," a spokesperson for the fire service told the Guardian. "We also want to develop a more fail-safe sprinkler system. I expect they will pass the tests but if they develop the building as they say they will, it will be a serious project.” While somewhat counterintuitive, timber can actually be quite resistant to fire. As Bentley explained: "Heavy timber and cross-laminated timber actually have built-in fire protection; dense wood will burn slowly, charring instead of catching fire all at once. Part of bringing a wood building up to code is providing enough wood so that even after fire produces a 'char layer,' there is still enough left to support the structure."