Engineered timber is lighter, stronger, cheaper and more sustainable than concrete. Courtesy UC San Diego.
With concrete being identified as one of the biggest contributors to CO2 emissions, the search is on for better, more sustainable building materials. Some designers are turning back the clock and using wood as a key structural element in their buildings. By Jeremy Torr.
British Columbia, Canada. July 2020. With all industries being hard-hit by the coronavirus pandemic, some countries are using the opportunity for a reset of their approach to traditional practice. For example, the Canadian province of British Columbia (BC) is working towards a new approach to building – one that will both ramp up new job creation and cut down emissions across the sector.
“British Columbia is a leader in the use of mass timber as an innovative way to reduce the carbon footprint of our building sector,” said George Heyman, Canadian Minister of Environment and Climate Change.
“Mass timber is key to diversifying and creating a resilient forest sector.” - Ravi Kahlon. Courtesy BC Govt.
The product he is talking about, engineered timber, is the new buzzword in many up and coming design houses; it uses structural-strength shaped and bonded timber laminates that can be prepared off-site to a consistently high standard, and then shipped to building sites when they are needed. It’s strong too – buildings using mass timber instead of concrete can be one-fifth the weight and of equal strength to a conventional building. This makes foundations and soil stabilization issues much less critical, even for multi-story buildings.
Using mass timber instead of concrete can also significantly speed up the construction of buildings. Plus it can boost new jobs by employing off-site prefabricators which in turn bring an added bonus in the form of reduced labour costs.
The province has also committed to ongoing expansion of the mass timber sector with the appointment of a new government Secretary for Forests, Lands, Natural Resource Operations and Rural Development. Ravi Kahlon will lead the initiative to boost timer constructions by liaising with local governments, industry and the construction sector. “Mass timber is key to diversifying and creating a more resilient forest sector,” said Kahlon. “I look forward to working with my government colleagues, the forest industry, construction sector and local governments to promote … wood products and their use in all our public and private sector buildings.”
Brock Commons House is just one innovative timber structure. Courtesy Wikipedia.
The added bonus to engineered timber is that it is valued at several times more than the traditional raw wood products that the province has traditionally produced. As part of this push back to timber, BC has introduced new building standards that will promote timber usage and use building codes that allow the construction of mass-timber buildings more than 12 storeys high. The province’s first forays into significant mass timber buildings are the new St. Paul’s Hospital and the replacement of the Royal BC Museum, both major government projects. Vancouver is planning the ambitious new Earth Tower, at 40 storeys the highest ever wooden building. Already the 18-story Brock Commons Tallwood House in Vancouver, and the 13-storey Origine Eco-Condos in Quebec have used mass timber prefabrications to make strong, sustainable structures.
“By focusing on mass timber, we have an opportunity to transition our forestry sector to high-value over high-volume production. This will mean opportunities for local workers, strong partnerships with First Nations and greater economic opportunity all while making a significant contribution to advancing (emissions reductions)” said BC premier, John Horgan.
“It is not just about being green. It demonstrates that change is possible.” - Ninotschka Titchkosky. Courtesy BVD Architects.
And it seems the word is spreading outside the innovators in Canada. In Sydney, software house Atlassian is planning to build itself a new 40-story office structure, using mass timber as a key component. “The (new) building will house up to 4,000 people and be constructed with a combination of mass timber, concrete and steel,” said chief architect Ninotschka Titchkosky. For a lower height building you can build totally in timber, but at 40 storeys we need to hybridise the structure,” she said.
The building, which will use timber to help achieve a 50% reduction in embodied (production embedded) carbon is also designed to run on 100% renewable energy and produce zero emissions. The architects say energy efficient design, natural ventilation, planted flora terraces, and on-site green power generation using solar panels will all help achieve this target.
“We are … strong advocates for sustainable design, smarter construction and human-centred environments,” said Titchkosky. “This (Atlassian) project is not just about being green. It will demonstrate that change is possible and has many advantages for the planet, our cities and businesses”