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What Wood You Build: The Untapped World of Mass Timber
Mjøstårnet, an 18-story mixed-use building in Brumunddal, Norway completed in March 2019, is the world’s tallest mass timber building. Mass timber is currently more common in European countries than in the United States.
Erin Doering | Clemson University
transformations of timber Mass timber has been in use since well before the recently-built Hotel Magdalena. This system of construction first emerged in the early 1990s in Austria, where softwood forestry is very common2. In Europe mainly, where it broadened in the 2000s, crosslaminated timber was developed for use in residential construction because mass timber was more sustainable than concrete or brick, while retaining a similar, firm material feel. Today, mass timber continues to steadily gain ground in Europe and Canada, with the rise of structures such as Vancouver’s Brock Commons and Norway’s Mjøstårnet.
The Hotel Magdalena in Austin, Texas designed by Lake Flato Architects is the first mass-timber, boutique hotel constructed in North America. The structural system reduces the energy of the structural components by using renewable materials and limits the carbon use intensity during the construction process by drastically shortening construction time.
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Completed in 2020, the Hotel Magdalena in Austin, Texas boasts generous outdoor spaces, wide exterior corridors, and private terraces for each guest room. The hotel will attract thousands of tourists a year due to its impeccable grassy gathering spaces, private suite gardens, and outdoor pool bar. But in spite of all its exterior glory, the most exhilarating thing about this hotel is what’s inside: supporting over 73,000 square feet of lavish hospitality, while creating a remarkable guest experience, is the structural system of the hotel: a massive, load-bearing assembly, made entirely out of mass timber wood1. Mass timber elements are thick, pressed layers of wood which create strong, structural, load-bearing components that can be built into panelized elements. They are usually fabricated using lamination, fasteners, or adhesives. The broad term “mass timber” encompasses products of abundant sizes and functions.
Disappointingly, it remains delayed in the US by anachronistic and overly prescriptive building codes, deficient domestic supply, and the small-c conservative thinking of the building trades. Many professionals feel strongly that these issues have created a lack of acceptance and awareness around mass timber2. Predictably, this is not the first time building trades have been skeptical of new construction methods. The midnineteenth century shift from “post-andbeam” to “balloon framing” marked a crucial change, not only in the history of wood construction, but also in the practice of architecture and building. Carpenters of the time saw the 2x4 studs that comprised balloon framing as flimsy “sticks” in comparison to their post and beam counterparts; yet the groundbreaking method caught on, since it took less time to fabricate each of the elements and erect them, all while keeping similar strength across pieces. Ultimately, it was the industrial revolution that allowed trees to be milled into the lumber that paved the way for this radical, innovative way of putting together a building. To contractors and construction workers, this must have
been as unsettling a notion as it was revolutionary. Although there was initial resistance, balloon framing eventually succeeded and is now the most popular residential construction method in the US. Who’s to say history won’t repeat itself? Mass timber might feel too unfamiliar in the industry at the moment, but as the realization of its benefits only increases its production, it can become the most widely used way to construct any type of building3. While potentially unexpected, the use of mass timber is definitely not unprecedented. “People have been building homes out of wood forever. More than 90 percent of single-family homes in America are made of wood. Still, because of wood’s limitations, more significant buildings like offices, schools and department buildings had to be made out of concrete and steel. Mass timber systems are changing that.” says Assistant Director of Clemson University’s School of Architecture, Dustin Albright5. It wasn’t until architects started using CLT to replace concrete and steel in bigger buildings, that mass timber began popping up in North America in the 2010s. Currently, in the U.S., mass timber can’t yet compete with stick-frame construction, which is cheap and ubiquitous. However progress is being made: a set of the latest changes that will enable mass timber structures up to 18 stories tall have been accepted and are expected to be formalized into the newest IBC code in 2021.2
move over steel and concrete: mass timber has entered the chat When it comes to a sustainable built environment, material choices matter. Wood is a great choice for a natural, renewable, and sustainable material for building, with a lighter carbon footprint than steel or concrete. However, the advantages of mass timber construction don’t stop there. The growing enthusiasm of builders, designers, and advocates seems to be chipping away at the opposition to mass timber. Where is their conviction coming from?
The concept of the primitive hut explores the anthropological relationship between humans and the natural environment as the fundamental basis for the creation of architecture. It contends that the ideal architectural form embodies what is natural and intrinsic.
IT’S IN OUR NATURE The fundamental attraction of mass timber is its instinctive connection to the human experience. Moreover, it contributes to healthy, sustainable environments, and requires a construction process that is simpler than conventional carbon-laden building methods. Mass timber embodies the central principles of biophilic design: the human inclination to be close with other forms of natural life. Since the wood in these projects doesn’t have to be wrapped or bolstered to meet code, it is usually left exposed. This is evocative on a primal level since wood has an apparent connection to nature. The ability to make that direct connection to nature in interior spaces is a colossal advantage, given the fact that we spend the majority of our time indoors, not outdoors. 47
WHAT WOOD YOU BUILD?
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OCCUPANT WELL-BEING The application of natural wood in mass timber buildings creates healthier and inspirational environments. Designing an interior environment plentiful with natural wood has a definitive effect on the autonomic nervous system, making occupants subconsciously more comfortable and relaxed. The benefits of connections with nature have been studied using diverse natural stimuli in a wide variety of settings, countries, and cultures. The overall conclusion is that nature relatedness—the instinctive sense of connection people have with the natural environment—is a universal psychological need. For example, a study conducted in British Columbia provides evidence that wood surfaces in an office lower the body’s sympathetic nervous system (decreasing blood pressure and heart rate), thereby reducing stress6. LITERALLY LIFE SAVING Mass timber’s distinctive characteristics also entail remarkable life-safety benefits. In the event of a fire, the natural density of mass timber will cause its exterior to char in a predictable way that effectively self-extinguishes. This allows it to retain interior structural integrity for several hours in even the most intensive fire. Mass timber buildings also typically weigh less than concrete and steel, which reduces risk of structural failure during seismic events4.
Mass timber is a new category of wood product that can revolutionize how America builds. It is composed of multiple solid wood panels nailed or glued together, which provide exceptional strength and stability.
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EFFICIENT CONSTRUCTION The simplicity and efficiency of the mass timber construction process differentiate it from traditional carbonladen building methods. Large-scale structural elements are prefabricated and delivered to the site ready to be assembled, crucially reducing construction time and waste. Prefabricated mass timber elements are assembled with less extensive construction sequences than their concrete or steel counterparts. This methodical staging process allows for fewer disruptions and complications, thereby demonstrating sensitivity to the surrounding community, plus earning brownie points with the project contractor4.
EXPERIENCE IS EVERYTHING Finally, mass timber systems offer significant experiential benefits. Large structural elements in warm wood tones evoke the comforting familiarity of a tree canopy. Due to their inherent density and composite attributes, mass timber contributes to sound control and acoustic dampening within a building. Mass timber products are hypoallergenic, enhancing a building’s air quality, and the enhanced humidity control of the material boosts the thermal comfort over baseline construction4.
the future is fir While the design and construction industry has been slow to adopt mass timber construction methods, academic institutions have been at the forefront of ongoing research and education. For example, Clemson University has been a leader in mass timber systems’ research and education, including crosslaminated timber, through its Wood Utilization + Design Institute (WU+D), as well as integrating the innovative construction method in their most recent studios. In the Fall 2020 semester, students in professor Dustin Albright’s studio course teamed up with professionals from southeastern design firm, LS3P, to explore the use of mass timber systems for school buildings. “The advancement of mass timber technologies has opened a new door for me in architecture. It’s a sustainable alternative to combat the negative environmental impacts that typical building materials can have on the environment.” says graduate student Bryan Hazel. The goal of the studio was twofold: to support student learning for the next generation of architects with a studio that blurred the lines between academia and practice, and to explore the use of mass timber in Southeastern construction projects. The students based their study
Section perspectives of graduate student Bryan Hazel’s design for the Forest Lake Elementary School for Clemson University’s fall 2020 fluid studio using a mass timber construction method.
around a real LS3P project: a new school campus and building at Forest Lake Elementary School in Columbia, South Carolina. The studio sat at the intersection of the topics of the physical learning environments and carbon emissions of buildings. The students examined the use of mass timber in the design of vibrant, healthy, forward-thinking school buildings. Students were tasked to research the process of mass timber production and construction at the start of the semester then used multiple precedent studies of innovative elementary schools and mass timber buildings to influence their designs. “It’s becoming more and more popular, so knowing how to work with this system is going to be increasingly valuable for our students.” claims studio professor, Dustin Albright5. While adoption and use of mass timber construction has been slow in the United States, it is a reliable method for the future of designing our buildings due to the growing need for sustainable practices in the industry and the world. It would be not only imperative for students to start learning and considering mass timber design and construction for their studio projects, but very reckless and irresponsible to overlook it. It is critical to not only prepare for, but also possibly create upcoming landscapes, cities, and buildings for the better. Mass timber presents and solves many possibilities and challenges we’re facing in construction today and in the future. The value of mass timber doesn’t stop at occupant well-being and beauty. It’s necessary for the future of the next
generation of architects and builders. This will inevitably not only be our best option, but our only option. Reducing embodied carbon of materials over the next few years is a particularly important strategy because it will help architects and designers meet large scale emission reduction targets recommended by global organizations. Wood is the only material sufficiently abundant and renewable to do the job.
References 1. Wood, Think. “Inside Hotel Magdalena the First Boutique Mass Timber Hotel - Gb&d.” Gb&d Magazine, GB&D Magazine, 13 July 2021, gbdmagazine.com/hotelmagdalena/. 2. Roberts, David. “The Hottest New Thing in Sustainable Building Is, Uh, Wood.” Vox, Vox, 15 Jan. 2020. www.vox.com/energy-and-environment/2020/1/15/21058051/ climate-change-building-materials-mass-timber-cross-laminated-clt . 3. Pollan, Michael. A Place of My Own: The Architecture of Daydreams. Random House, 2008. 4. “Mass Timber Architecture.” Pickard Chilton, www.pickardchilton.com/ expertise/architecture/mass-timber-architecture. 5. “Clemson Architecture Students Partner with Top Design Firm ...” The Times and Democrat, 22 Apr. 2021, thetandd.com/news/local/state-and-regional/clemsonarchitecture-students-partner-with-top-design-firm-to-pioneer-sustainableconstruction-process/article_a7268cf3-713c-54f9-8348-3470c4982a71.html.
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