Australia imports $7 billion of timber a year

That’s an economic and climate problem we can fix.

By Professor Greg Nolan, previous Director at the Centre for Sustainable Architecture with Wood, UTAS

We have a renewable, carbon-storing Australian-grown building material, produced to world-leading standards. Choosing to grow it and use it is sound economics and sound climate policy.

As an architect, I spend a lot of time thinking about the materials that we use to make our buildings, as the choice has consequences far beyond the building site. Constructing and operating buildings generates roughly 40 per cent of global carbon emissions, and about 40 per cent of these emissions result from making energy-intensive building materials such as concrete, steel, glass and aluminium. However, there are readily available building materials that avoid these emissions, are renewable, and store carbon: timber and wood products.

A growing tree draws carbon out of the atmosphere and sequesters it in its wood. Then, timber used in a building stores this carbon for as long as the building stands. This storage is measurable and considerable. The University of Tasmania’s new building, The Forest, cut its embodied carbon by about 44 per cent against a conventional design, in large part by building in large-dimension glulam and other timber components. Recent studies have indicated that to reach carbon neutrality by 2050, Australia’s building construction sector needs to make 30 per cent of its buildings from mass timber. The timber stores atmospheric carbon and the high carbon emissions from alternative materials are avoided.

The market has begun to price the difference: in low-carbon timber buildings, tenants, including ASX-listed companies now obliged to report their emissions, have paid a premium per square metre, because a lower-carbon timber-rich building is a better place to work and this makes for higher productivity and a better balance sheet.

The climate science is unambiguous about wood’s role in low-carbon human society. Hans Joachim Schellnhuber, founding director of the Potsdam Institute for Climate Impact Research, describes trees as “a technology of unparalleled perfection” and argues there is “no safer way of storing carbon”, if we engineer the wood into modern building materials and smartly manage harvest and construction, in his words, “we humans can build ourselves a safe home on Earth.” The Intergovernmental Panel on Climate Change (IPCC) reached the same point: a forest managed for a sustained yield of timber while maintaining or increasing its carbon stocks delivers “the largest sustained mitigation benefit.”

In short, growing and harvesting sustainably managed forests as the resources for effective building materials production and building design solutions is the preferred low-carbon option for Australian construction sector.

Here is where Australia’s settings run against its own interests. We don’t grow enough material and want to increase restrictions on access to forests that are managed to world’s best practice. We import around $7 billion of timber and wood products a year and run a trade deficit of about $4 billion. And what we import is increasingly from countries with weaker environmental standards than our own. With tariffs on timber now emerging in major markets and freight costs climbing, that dependence is a growing economic risk, and it flows directly into the cost of building a home at a time when housing affordability is a national emergency. A sovereign supply of a renewable building material is not parochial; it is strategic.

Sovereign supply isn’t just about having the raw material. It’s about having and maintaining the capability to process it into reliable building solutions. Turning trees into timber and wood products, and into the engineered mass-timber components that large low-carbon buildings rely on is specialised manufacturing, usually found in regional areas. Australia has very little of it. Let that capability wither, or deliberately extinguish it, and the work and the value flows to Europe, China, or others who will harvest their forests. Re-shoring construction’s carbon savings means keeping the factories as well as the forests.

There are also issues we tend to avoid in Australia. We want carbon neutrality but won’t meaningfully discuss solutions to hard-to-abate emissions like embodied carbon in building materials. Our demand for timber and wood products is rising, not falling. If we don’t grow and harvest the forest here, under some of the most rigorous standards in the world, and maintain the capacity to manufacture products, we simply import it. We offshore the environmental cost to someone else’s forest and pass up the regional employment and economic benefits we could have maintained or secured.

Forests can be harvested and successfully regrown in a dynamic landscape. And the assumption that local harvesting must mean ecological loss deserves scrutiny. Research by Tasmanian conservation scientist Dr Marie Yee found species richness in regrown native forest broadly on par with old growth forests, because biodiversity depends on a mosaic of forest ages that landscape-scale planning is designed to sustain. That does not make every outcome benign, as some species need active, science-led protection, and generally receive it, but it does mean responsibly managed native forestry and biodiversity are not opposites. Native and plantation forestry have very low biodiversity impacts when compared to other economic activities in our landscapes and can actively regenerate biodiversity in degraded areas.

Sustainably managed native and plantation forests are essential to supply Australia’s diverse timber needs. They are complements, not substitutes. Each provides a different processing resource and yields products that our building construction sector needs. Pretending otherwise simply sends us back to the import queue and can make us complicit in forest degradation in other parts of the world while undermining regional resilience in Australia.

We can keep importing product, or we can value and expand what we already have: a renewable, independently certified, carbon-storing material, grown to best practice, that builds healthier places to live and work and lowers the emissions of the most carbon-intensive sector in the economy. For a country serious about both its climate targets and its housing supply, that should be an easy call.