Brisbane 2032: Creating lasting impact through transformative infrastructure
Aurecon shares insights on how the 2032 Brisbane Games can deliver legacy infrastructure and lasting economic, environmental and community value.
Change your location to view content tailored for you.
Due to a tree’s ability to store carbon until it rots, decays or burns, designing and constructing buildings using timber significantly reduces potential greenhouse gas emissions. Particularly if sourced from sustainably-managed forests, timber building products are an environmentally friendly choice. But more than that, timber can be a truly circular economy product.
Circular economy is a framework that supports businesses and communities to thrive in a climate and resource constrained world by designing out waste and pollution, extending the use of assets and materials, and regenerating natural systems. It is a system-based thinking approach, regenerative by intention and design.
Decreasing reliance on finite materials to prioritise renewable resources, such as timber, is a key concept of the circular economy. When mass engineered timber (MET) is harvested from certified sustainably managed forests, it can play an important role in the circular economy and can have a lower carbon footprint than traditional building materials.
MET is generally constructed through the gluing together of multiple layers of wood, allowing for thinner and lighter layers of wood. This reduces the amount timber needed, enabling resource conservation. Due to its engineered nature, it is less susceptible to warping or splitting, increasing its lifespan and by extension, longevity of buildings.
MET also allows for modular design and construction, helping to design out waste and pollution at the start. Modular timber buildings are assembled from prefabrication which reduces waste and can support disassembly at end-of-life, enabling components to be re-purposed. By using MET in a circular economy approach, we can promote sustainable forest management, design out and reduce waste whilst conserving finite resources.
MET is lightweight yet strong and requires less carbon dioxide to manufacture, as compared to steel and concrete. On average, producing a product from steel requires 19 times more energy than from timber; 45 times more to produce a plastic product and 85 times more to make an aluminium product (Timber NSW).
However, even though MET is a highly sustainable building material that also encourages a greater sense of wellbeing for building occupants, according to the biophilia hypothesis, which involves increasing connectivity with nature by using natural elements indoors, questions still exist about its inherent benefits as a construction material. In this video, we debunk some of the most prevalent myths about MET.
Busting the myths on timber buildings – Aurecon senior structural engineers debunk some of the myths on timber buildings – from them not being fire resistant, to being susceptible to termites!
As we need to build 10,000+ buildings a day to cater for a 10 billion world population by 2050, and building and construction represent almost 40 per cent of all carbon emissions, there is a clear case for using timber in greater proportions.
There is a misconception that timber is an unsafe building material, however, timber contains some inherent qualities that make it safe in a fire event. For instance, timber is an excellent insulation material, meaning that it doesn't easily allow heat to pass through it. Massive timber is difficult to ignite (think about how hard it is to light a large log on a fire!).
Also, timber chars from the outside, leaving an insulating layer of charcoal and sound timber underneath that maintains its integrity. This also means that it burns slowly, making it a very predictable material in a fire event, allowing time for evacuation. Australia's Nation Construction Code sets Performance Requirements for timber that ensures buildings constructed with timber are safe in the event of a fire.
Large timber buildings are usually constructed with reinforced concrete groundworks to create separation between the timber and the ground and with no concealed entries that allow termites to enter. This is the case with 25 King, Australia’s tallest commercial timber building, which is constructed on a concrete podium.
Timber can also be treated against insect attack and this is a key part of any strategy, and is in fact mandatory in some parts of the world.
MET can and should be sourced from sustainably-managed forests, which actually improves a forest’s carbon sequestration rate, as opposed to allowing forests to decay or burn naturally, releasing carbon into the atmosphere.
Timber has a lower carbon footprint than traditional building materials. Trees actively sequester carbon from the atmosphere while growing, and when they are cut down for use as building materials, the carbon is ‘trapped’, unable to escape into the atmosphere as carbon emissions.
MET products are strong; some structural load-bearing elements have a higher strength to weight ratio than typical concrete mixes. When the natural shrinkage and expansion of timber is appropriately considered in the design, timber performs well as a structural system. Where buildings are designed with timber cores (usually the main lateral load resisting system), diagonal timber bracing can be implemented to resist lateral loads while also providing an architectural feature.
MET construction is faster, safer, quieter and creates less waste as it uses precise off-site prefabrication. As off-site prefabrication occurs in the controlled environment of a factory, with modules delivered to site, this can lead to fewer truck movements and decrease construction time by up to 50 per cent and improve safety on site.
It also reduces site noise and waste. MET construction also lends itself to the use of automated construction techniques, such as robotics, which many argue could be the future of construction.
Maintenance needs to be considered in the design of any building. Often a high-cost material has lower maintenance costs and vice versa so decisions need to be made about the balance between upfront capital cost and ongoing maintenance costs. The key to the durability of timber is moisture, so generally enclosed timber elements within a building will last for the accepted design life of any building, which is typically 50 years.
Large timber buildings are usually constructed on a concrete podium and the external facade is clad in glass or other material so the timber is not exposed. Any external timber elements can be protected by an additional layer of non-porous material.
Timber consists of a network of interlocking cells that convert sound energy into heat energy, meaning that timber has a greater sound dampening ability than many other building materials. While concrete walls bounce sound, creating an echo, timber tends to 'absorb' sound which is why it is often used to clad walls and ceilings in public buildings.
The Sydney Opera House, whose theatres are lined in timber acoustic panels, is a great example of the acoustic performance of timber. Raised floors and floor coverings can further reduce any potential impact of noise, particularly in office buildings.
Mass engineered timber is a different material to concrete and steel and has its own unique properties. Experience in designing and building with MET is important to ensure serviceable and durable buildings.
Aurecon has amassed an enviable track record in successful timber design over the past 35 years, including designing Australia's tallest commercial timber building, 25 King; Australia's tallest residential timber building, Boola Katitjin at Murdoch University; and one of the world's largest timber buildings, Nanyang Technological University Academic Building South in Singapore.
Director, Innovation
Buildings Structures Practice Leader – QLD, Australia
Buildings Structures Practice Leader – WA & NT, Australia
Principal, Sustainability – QLD, Australia
Senior Consultant, Sustainability – Australia
Aurecon shares insights on how the 2032 Brisbane Games can deliver legacy infrastructure and lasting economic, environmental and community value.
This fact sheet compares the community and environmental impacts of wind farm projects, and how ecologically sensitive design can deliver better outcomes.
How engineering and construction projects are evolving to champion biodiversity, through early planning, advanced technologies, and ecosystem stewardship.
