June - July 2021
Let science lead the way Forestry Minister Stuart Nash is well qualified to advance the cause for wood but 20 years in the sector does not qualify him to close one eye when it comes to complementary options, says publisher Mike Bishara
MATERIALS
Scion Innovation Hub - Rotorua
Practical visions for the future – a case for steel The Heavy Engineering Research Association (HERA) maintains that design should dictate material, advocating for the right material based on design that has been tested, consented and peer-reviewed where appropriate. Chief executive Troy Coyle says these decisions should not be dictated by government or industry bodies but by architects and engineers – “those at the coalface who are walking the line of design, performance, and seismic, sustainability and other standards every day. Some of the conversation suggests that a ‘wood first’ policy would help New Zealand do better against emissions targets. In fact, both the steel and concrete industries are aggressively decarbonising while delivering resilient buildings. While both materials have significant embodied carbon footprints, their life cycle carbon emissions improve due to their resilience, ability to enable lower operational carbon emissions, and in the case of steel, its infinite recyclability. Further, steel offers extremely long lifetimes, which means that the carbon is amortised over a longer period. 12 propertyandbuild.com
If our goal is to meet our emission targets, move to a low carbon economy and a circular economy, we need to stop focusing on embodied carbon and focus on lifecycle carbon. Steel is surprisingly low-carbon over its lives, is 100 percent recyclable and can be infinitely recycled without loss of quality. In New Zealand, 72 percent of steel is currently recycled. Lower-value steel scrap can be converted into high-value steels by using appropriate processing and metallurgy, and there are emerging technologies (locally and internationally) that have the potential to significantly reduce the carbon footprint of both materials. The New Zealand steel industry also strongly delivers to the Living Standards Framework. As for HERA’s own work, we are launching a zero carbon, steel-offsetting programme, which will also include steel reinforcing used in concrete; and a carbon emissions calculator, independently developed and based on verifiable data, which allows companies to offset embodied carbon emissions and offer zero-carbon steel. We hope that this will refocus the
conversation away from embodied carbon comparisons and more to what matters – net carbon emissions of the life of a building or structure. While wood is absolutely right for many jobs and applications, mandating its use for all projects could create economic and other problems. Yes, our future buildings must have a low-carbon footprint, but it is just as essential that they are resilient to our changing climate, and steel and concrete offer resilient buildings. Steel and concrete are essential for supporting high-value jobs, community investment and economic growth. In fact, MBIE’s own Manufacturing Report shows that there are 30 percent more jobs in metals manufacturing than there are in wood and paper processing, and that the bulk of the growth is regional. Based on this and other economic factors, Minister Nash’s expressed concerns about supporting regional development, national employment, sustainability and emissions reductions goals are more achievable with a practical, combined approach than with one which prioritises a single material.
