nation of CLT panels, glulam elements and ‘Brettstapel’; the Earth Sciences Building in Vancouver uses an OSB-type laminate in its floor panels as composite with a concrete topping; the Massey University building and LifeCycle Tower in Dornbirn use panels with laminated timber webs and concrete toppings.
Since 2005, various high profile landmark buildings have been realised in CLT technology and the construction system is now getting more and more established in Europe, the UK and Canada. The construction sector’s focus on embodied energy and carbon storage has increased recently.
Wood is a rapidly renewable resource. Currently, CLT structural timber is made from wood of the managed pine forests of northern Europe and Scandinavia. But, as global carbon will become an important commodity, it could be likely that China will start planting mega-forests on a scale the world has never seen.
Technology itself is not the main problem identified; the main barriers are the slow uptake by industry and consumer resistance to denser inner-city living and new construction materials/systems. For instance, further research is needed to analyse whether residents are more likely to accept higher densities when they know that the density is caused by very green buildings? It is essential to consult the community, for example in neighbourhoods earmarked for higher density and major developments. Studies of international ‘successful’ cities have shown that those that enjoy broad community support for their city’s policies have both consulted and developed consistent plans over time. The recent report by the Grattan Institute Cities: Who Decides (2010)  found that encouraging the community to meaningfully participate in the decisions that governments make about the city is fundamental in developing plans that are embraced and supported by the community. This includes the development of thoroughly researched alternative scenarios that are canvassed publicly: articulating a new Australian dream for the 21st Century, to succeed with urban infill projects proposing higher densities and multi-storey timber construction. It is about a sustainable approach to accommodating population growth in cities, while also recognizing the need for additional research on the user viewpoint. The general problem of Australians’ historic resistance to apartment living (which has much to do with the apartments’ poor design, small size, tall shape, noise and high cost), and the lack of experience with infill sites in Australian cities, mean we will need to learn how to do infill better and gain more knowledge in this area.
The case studies reviewed make a strong argument for timber in the urban context. But the cases also show that there is still a need to instill confidence in the performance of solid wood panel buildings as designed, so that they will be accepted in Australia, by professionals required to certify construction to the country’s standards and by the market. From the perspective of residents, social acceptance of CLT buildings will be influenced by factors affecting liveability, comfort and the consequent socio-economic outcomes. For example, we still lack knowledge about the public perception of CLT buildings for infill development in Australia and their performance in all conditions, including heat waves. Another question is: how far do income, education and age of residents play a role in the level of acceptance and awareness of green construction methods using CLT panels?
Both the general public and the architectural community lack knowledge about the design of CLT buildings and the impact of various design features on the carbon footprint of their use for infill development compared to other modern methods of construction. Education of architects and planners is everywhere lagging behind. Educators should be developing new courses that focus on research methods into new materials and low carbon construction systems, aiming to reposition future architects as more knowledgeable (and again, as influential) in the construction industry.
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