With 18 stories and 53 meters height, the recently completed Brock Commonsdormitory of the University of British Columbia in Vancouver, Canada, is the world’s tallest timber tower.
Recent advances in solid wood panel technology, specifically in cross laminated timber (CLT) materials, have fueled an unprecedented boom in the construction of wooden buildings over the last few years. The development of much stronger formaldehyde-free adhesives combined with an innovative 90-degree cross-lamination pressing have enabled the manufacture of wooden slabs strong enough to replace reinforced concrete floors, exterior shells, and the load bearing structure of any building.
Developers, architects, and builders are jumping en masse on the CLT bandwagon – in the last five years, several projects have vied for the title of tallest wood building – from the 10 story, 32 meter high Forte condominium block in Melbourne – completed in 2012 – to Cube in London, a 10 floor, 33 meter block of flats (2015) and the 14 story 53 meters high Treetapartment building in Norway’s Bergen (January 2016).
A number of other projects are in the works, including the 21 story, 73 meters tall Haut building in Amsterdam (construction to begin in 2017), the 24 story, the 84 meter HoHo office building in Vienna (construction started in October 2016), the proposed 41 floor and 133 meter Tratoppen in Stockholm and theOakwood Tower in London, an 80 story, 300 meter tall skyscraper proposal. If and when given the go-ahead, the Oakwood Tower will be London’s second tallest building and the tallest wooden structure in the world.
Several factors are driving the boom in high-rise wooden buildings, beside the fact that, as mentioned, technological advances are making thempossible: the novelty effect of seeing a wooden high-rise building, which still guarantees attention to the projects – even though, as the competition for being the highest building shows, that attention is becoming harder to ensure.
Beyond marketing, building with prefabricated CLT elements helps to reduce construction time and the transport of building materials to construction sites. But these advantages only help to counterbalance the higher cost of CLT elements as compared to concrete.
The biggest advantage of CLT is currently not entering cost calculations: it has been estimated by Skidmore, Owings & Merrill (SOM), the architecture firm responsible for some of the world’s highest skyscrapers, to have a carbon footprint 60-75% smaller than that of a steel and concrete building. Hopefully, the need to satisfy future demand for CLT will lead to the planting of new forests which, while growing, will absorb CO2.