US President Barack Obama putting his weight behind the development of wooden buildings.
The White House Rural Council and the United States Department of Agriculture (USDA) have announced a climate-driven initiative that would see architects, builders and engineers trained in the benefits of wood as a structural material.
Wood is already gaining ground as a popular material in tall building construction. The efforts of the USDA to support its advancement aligns with Obama’s Climate Action Plan, which preserves the role of forests in mitigating climate change.
“Wood may be one of the world’s oldest building materials, but it is now also one of the most advanced,” said Agriculture Secretary Tom Vilsack. “Building stronger markets for innovative new wood products supports sustainable forestry, helps buffer reduce greenhouse gas emissions, and puts rural America at the forefront of an emerging industry.”
“Presently, the market for wood and other related forest products supports more than one million direct jobs, many in rural America. As these markets expand, so will the economic opportunities.”
The Forest Service has invested $1 million and will work with WoodWorks, a not-for profit organisation that provides industry technical support, education, and resources related to the design of modern wood buildings.
Beyond the training component of the project, the USDA also plans to launch a prize competition for entrants to design and demonstrate the architectural and commercial viability of utilising wood in tall buildings.
The Binational Softwood Lumber Council, another not-for-profit partner, has committed an additional $1 million for the competition. Priority will be given to applicants who source materials from rural domestic manufacturers and domestic, sustainably managed forests.
According to some industry estimates, a three to five-storey building made from emerging wood technologies reduces emissions as much as taking 550 cars of the road for one year.
Wood-based designs also improve energy efficiency, thereby reducing energy consumption for heating and cooling.
Canadian architect Michael Green is world-renowned as a wood building advocate, and refers to traditional steel and concrete as “old world” materials.
In a TED talk last year, Green noted that steel use is responsible for about three per cent of man’s greenhouse gas emissions, while concrete is responsible for over five per cent.
He said a typical 20-storey concrete building emits 1,215 tonnes of carbon dioxide, while wood sequesters 3,150 tonnes of the gas for a net difference of 4,365 tonnes.
“That’s the equivalent of about 900 cars removed from the road in one year,” he said. “We are at the beginning of a revolution, I hope, in the way we build, and this is the first new way to build a skyscraper in probably 100 years or more.”
In Australia, the conversation on wooden skyscrapers was again ignited during Green Cities, an annual conference co-hosted by the Green Building Council Of Australia and Property Council of Australia.
Melbourne currently holds the title for the world’s tallest timber apartment building, Forté, which stands 10 storeys tall and is constructed from 760 panels of certified and manufactured cross-laminated timber (CLT) .
Anissa Farrell, an architect at Conrad Gargett Riddell, believes cross laminated timber has the greatest innovation potential for high-rise building.
“It’s an alternative to a structural system or the convention, it’s a prefabricated panel element that has low bearing capacity similar to that of precast concrete but is 20 per cent lighter,” she said.
Farrell adds the price of timber is comparable to concrete precast panels and notes CLT holds good thermal insulation properties when it burns.
On its website SmartStruct, says that when CLT is completely exposed, it has excellent fire resistance. There is also the opportunity to install fire resistant lining materials for further fire protection.
Green spoke of deforestation in his TED talk, pointing out that sustainable forestry models need to be implemented in which the “right” trees (those with fast growth cycles) are cut down. He added that 20 North American forests are able to grow enough wood for a 20-storey building every 13 minutes.
Murray Grove in the UK reaches nine storeys in height, and a 34-storey wooden skyscraper was proposed for Stockholm last year. Green also predicts that using a hybrid system, wooden buildings can move beyond 30 storeys.
With the White House showing an interest in the built environment’s role in its climate strategy, there is perhaps an unsung hope that other governments across the globe will begin recognising structural alternatives as cities continue to struggle with atmosphere pollution and climate change.