By Dr Troy Coyle, CEO, HERA
As our planet faces the undeniable impacts of climate change – intensifying storms, heatwaves and devastating wildfires – it becomes increasingly clear that every sector must boldly transform to mitigate these effects. Among these, the construction sector stands out not only for its potential for significant environmental impact, but also as a beacon of change.
In Aotearoa New Zealand, our construction sector is responsible for 20 per cent of national greenhouse gas emissions. Recognising this, the government has set ambitious targets to halve carbon emissions by 2030 and achieve net zero by 2050. At HERA, we see this as more than a mandate; it is an urgent call to action and an opportunity to lead by seeking innovative tools, technologies, and frameworks to transform the construction and building sector, and achieve carbon reduction targets in time.
It is why we have undertaken a $772,000 project entitled ‘Circular design for a changing environment: a design framework to reduce construction waste, lifecycle embodied carbon, and to enhance the circular economy for construction materials, with a pilot for low-rise buildings’. We have received $150,000 from BRANZ, funded by the Building Research Levy.
This project is set to pioneer a new horizon in sustainable construction by developing a comprehensive design guidance framework that is material-agnostic – equally applicable to steel, timber and hybrid systems, and designed with the flexibility to adapt across different building types and sizes. We are also piloting this framework for use in providing specific guidance for low-rise steel and steel‑hybrid designs.
How will we pioneer a new horizon in sustainable construction?
A comprehensive review of the current low-carbon strategies, solutions, and recent research and developments has already been undertaken. A draft design guide framework has been developed and is currently being peer reviewed.
While this framework will offer generic pathways and strategies, and pertinent low-carbon design solutions, specific design guidance will need to be tailored to particular materials and structural systems that align with the applicable design standards and building codes. As such, while the framework may have global applicability, it will be essential to verify the compliance of existing specific design guides developed overseas, with the design standards, building codes, and regulatory framework of the end user’s country. To this end, we will pilot the use of the framework in the application of low-rise buildings, with a focus on steel and steel-hybrid systems, with the learnings from the pilot informing improvement to the framework.
This framework is not just a template; it is a strategic tool that places a strong emphasis on circularity and sustainability in building design. By prioritising strategies with the highest potential for reducing carbon emissions, we are setting a new standard for what building design can achieve.
In practical terms, this means integrating life cycle assessments more seamlessly into the design process – allowing architects and engineers to make informed decisions that balance functionality with environmental impact. Our pilot projects in low-rise buildings are already showing promising results, demonstrating that smart design can already reduce carbon emissions significantly.
Our learnings so far
A recent case study of an office building in Ōtautahi Christchurch based on a steel-concrete composite system illustrates the tangible benefits of this approach so far. Our preliminary analyses predict substantial reductions (up to 50 per cent versus a standard design) in carbon emissions, proving that our strategies are not just theoretical, but are also immediately applicable.
As we move forward, our commitment remains firm: to transform New Zealand’s built environment into a model of sustainability that others can follow. It is a journey we are proud to lead, fuelled by innovation, guided by science and driven by the urgent need for environmental kaitiakitanga (guardianship).
HERA’s circular design focuses
HERA is an impact-led independent research association focused on heavy engineering, and its applications in manufacturing and construction. When it comes to sustainability, HERA’s role is to stimulate innovation to futureproof our industry with two key projects – the Endeavour Construction 4.0 rangahau and the Australian Composites Manufacturing Cooperative Research Centre project, both having a strong focus on the circularity of steel and steel composites, and life cycle assessment – and how steel contributes to this.
HERA has also commissioned thinkstep-anz to assess steel recycling in New Zealand, showing that an impressive 85 per cent of steel scrap is recycled here, and that recycling steel scrap produced in Aotearoa provides significant environmental benefits – despite the need for transport to overseas recycling facilities.
The study also showed that the amount of steel scrap collected for recovery is critical to the overall benefits of the recycling system.
About the author
Dr Troy Coyle brings more than 20 years’ experience in innovation management across a range of industries, including materials science, medical radiation physics, biotechnology, sustainable building products, renewable energy and steel. She is a scientist with a PhD (University of New South Wales), and has training in journalism and communications.