It looks like city-dwellers are not the only people looking for a tree change.
Developers are considering a tree change too, with timber featuring as a significant building material in new high rise buildings.
The first commercial office building in Australia made completely from timber will be built by Lendlease as the gateway to its multi-billion dollar Barangaroo development in Sydney.
The six-storey International House Sydney will be made from engineered wood – Cross-Laminated Timber (CLT) and Glulam (glue laminated timber) which come from sustainably managed forests in Austria. [Source: http://www.smh.com.au/business/property/first-wooden-commercial-office-tower-to-rise-in-barangaroo-20160616-gpkmyk.html]
This new generation of timber buildings uses manufactured, engineered materials collectively known as ‘mass timber’.
The most common of these is cross-laminated timber (CLT) — layers of wood, glued together under high pressure with the grain of each perpendicular to the one before. The end product is strong and rigid, unlike raw timber, which will warp and weave over time.
“CLT, just by the very nature it’s assembled, means it’s quite dimensionally stable,” Arup engineer Craig Gibbons said.
That stability means mass timber components can be manufactured to the precise dimensions required by a project, and delivered to sites with a high degree of confidence they will assemble as planned.
This new generation manufactured timber can be used to create buildings much, much taller
Norway currently boasts the tallest timber building with a 14-storey timber high rise called Treet. Canada hopes to eclipse that later this year with an 18-story timber dorm building at the University of British Columbia, soon to be followed by the 21-storey Haut building in Amsterdam.
There is even talk of timber-constructed residential high rises up to 40 storeys in Stockholm.
For anyone with visions of a Towering Inferno disaster can rest assured that research has shown heavy timber elements exhibit different fire performance compared to light timber and achieves an inherent fire resistance by formation of a charring layer.
The real concern about the large scale use of timber for construction is supply.
Dr Philip Oldfield, Senior Lecturer in the Faculty of the Built Environment, University of New South Wales cautions that in terms of sustainability, using timber is only useful if for every tree you fell, you replace that with a similar tree. A future of timber towers requires us to be planting these trees now.
Beyond the obvious environmental advantages of timber, the material also presents additional benefits in terms of design and liveability.
“Timber can bring a warmth and natural quality to interiors so often lacking in high-rise,” he said.