Stick frame timber making its mark
Timber, one of the most primitive construction materials on Earth, is undergoing a renaissance in its use within the built environment both in Australia and around the world.
The case for timber is very compelling. It is a sustainable material that can be replenished for future generations. Many argue that timber is ecologically sound, moreover timber buildings can act as carbon sinks and absorb CO2. It has remarkably good strength to weight ratios, is durable, performs well under fire conditions, acoustically and thermally, and is light-weight and easy to handle on site.
While CLT has enjoyed an increased profile since its introduction into Australia five years ago, it is, in fact, the more locally available and frequently used Laminated Veneer Lumbur (LVL) and Glulam “stick frame” components that are enabling a wider variety of structures in the marketplace. Timber works best when considered as part of a suite of components and materials that define a building structure. Glulam and LVL clearly lend themselves to column and beam elements and, in doing so, can provide open plan spaces that compare favorably against traditional materials.
Andrew Dunn, CEO of the Timber Development Association and a key proponent of engineered timber in Australia, reflects on the wave of interest for timber buildings: “If you asked me 12 years ago, if we would be discussing mid-rise timber buildings of a height varying from 6 to 25 storeys, I would have laughed out loud.”
The education sector has responded to engineered timber with gusto. RMIT have recently welcomed a four storey timber stick framed student accommodation at their Bundoora campus by RMA Architects, and a 4 storey open Garden Building by NMBW Architects at their city campus as part of the New Academic Street upgrades. Both buildings boldly expose the process of the timber stick frame assembly and, in both instances, were largely prefabricated and erected in live and constrained sites. Exposing the timber in such environments presents no greater fire risk than steel or concrete, in so far as the timber will char at a predictable rate (typically 0.4-0.67mm/min) and can be designed to support fire loads without great penalty.
A further recent addition is the striking the Macquarie University Incubator which represents a prefabricated single-story open plan building housing hot desks, collaboration spaces and conferencing facilities for translational academic-industry activity. The timber frame is expressed throughout the building and largely defines the character of the building.
“We looked to timber as the main construction material for The Incubator because of its capacity to be beautifully engineered, swiftly fabricated to high quality, and for its potential for future dis-assembly and relocation. The majority of components were prefabricated off-site to ensure rapid construction on-site and minimal disruption to the concurrent university semester,” said Luke Johnson, Principal Architect from Architectus.
Perhaps the most compelling driver for timber are the benefits that stem from biophilic design. People warm towards timber, and the consequent well-being and productivity that comes from an empathetic workplace provides an immense point of difference.
“The reality is that everyone loves the building and it has a visceral impact. The demand for start-ups to come into the space is overwhelming,” says Professor David Wilkinson, Deputy Vice Chancellor, Corporate Engagement and Advancement at Macquarie University.
And according to Dunn, the future is bright. As he says, “up until recently, timber was occasionally used in pools, sports halls, churches, i.e. activity with bigger budgets. Now we have three materials (timber, steel and concrete), not just two”.