Concrete sector grows carbon critical

Concrete NZ’s 2024 Sustainability Report says that the decarbonisation of New Zealand’s cement and concrete sectors is accelerating.

Concrete NZ Sustainability and Policy Director Tim Kleier says the industry has set ambitious goals, including a 44% reduction in direct and electricity-related CO2 emissions by 2030 (compared to a 2020 baseline) and a net-zero carbon industry by 2050.

“Across the country, Concrete NZ’s members are modernising their operations, from upgrading batching infrastructure and optimising material inputs, to deploying electric vehicles and embracing digital technology for real-time quality control.”

The rapid uptake of Supplementary Cementitious Materials (SCMs) was a standout result, Kleier says. One example of SCMs is the use of alternative low-carbon binders, such as granulated blast-furnace slag or fly ash, which reduces reliance on traditional Portland cement.

“SCMs now account for 6.6% of all binders used in ready mixed concrete, more than four times the 2020 baseline share. With SCM infrastructure now in place to support the 2030 Roadmap target, the sector is well on its way to delivering tangible emissions reductions.”

Despite slower building activity and economic uncertainty ramping up, the report says momentum for decarbonisation remains strong.

The 2024 report draws on contributions from producers representing around 80% of ready mixed concrete volumes, with substantial participation from precast, masonry, and reinforcing processors.

The 2021/22 report looked at the SCM value chain’s establishment. 2023 looked at the growing uptake of SCMs in concrete mixes. The focus of the 2024 report shifted to efficiency in concrete production and delivery, which Kleier says is a critical lever in reducing the industry’s footprint.

“The results confirm that sustainability and performance can go hand-in-hand, delivering lower-carbon outcomes without compromising durability, strength, or cost-efficiency.”

The report highlights key cases of industry innovation. Developed using advanced processing technology, Kayasand Engineered Sand™ transforms quarry by-product into high-performance engineered sand, reducing reliance on natural sand, an increasingly scarce and environmentally sensitive resource.

By adopting digital technology to automate and optimise delivery, Bridgeman Concrete and Verifi have improved efficiency and cut emissions across operations, showing how smarter systems in the delivery cycle can achieve meaningful carbon reductions.

Bullocks Group take a multi-pronged approach, combining solar generation, electric loaders, circular practices in water and the use of recycled aggregates. Its flagship initiative, in partnership with HR Cement, is the adoption of Eco-Cem™ cement, enabling Eco-Max concrete that can cut around 90kg CO2e per cubic metre at a 40% blend, without compromising strength or finish quality.

“These examples demonstrate how local companies are embracing technology and innovation to reduce emissions, strengthen resilience, and support the shift towards a circular economy.”

Kleier said the report also highlights the next stage of the industry’s journey. Building on the 2050 Net-Zero Carbon Roadmap, the Transformation to a Low-Carbon Concrete Industry project is well underway. Due for release in early 2026, it will recognise specific opportunities and actions to accelerate progress.

Concrete NZ Chief Executive, Rob Gaimster, said the 2024 Sustainability Report was further proof that collaboration is turning ambition into action.

“We are now tracking progress with more confidence than ever before, thanks to the commitment of our members.

“The breadth of data and innovation highlighted in this report demonstrates a real industry-wide determination to reduce emissions while continuing to deliver the durable, resilient concrete that New Zealand needs.”