Verry cites global data showing cement and livestock each represent 7-8% of global emissions. The context in New Zealand is quite different: livestock accounts for about 49% of gross emissions, while cement and concrete – including imports – contribute under 2%.
Our sector is transparent about its emissions footprint and is already implementing solutions, as outlined in its 2050 Net Zero Carbon Roadmap.
Low-carbon concrete is becoming a regular occurrence throughout New Zealand. Examples are the low carbon precast for social facilities at St Leonards Park in Hastings, the Oakley Creek Slip and shared path remediation, the first certified passive house office building, The Dunlop Hub in Wānaka, and the mixed-material LowCO homes at the Waiata Shores development.
Anyone is invited to approach local concrete manufacturers and to specify concrete with lower-embodied emissions. Concrete New Zealand runs regular events to provide specifiers with the tools and knowledge required.
In order to support a consistent uptake for low carbon products, Concrete New Zealand has publicly supported the BfCC programme, and we’ve endorsed the New Zealand Green Building Council’s voluntary embodied carbon methodology as an interim solution. This means emissions can be considered in building design and material choices right now.
Verry incorrectly asserts that most cement is manufactured offshore and as such is not touched by the Emmissions Trading Scheme (ETS). Most of New Zealand’s cement is actually produced locally, creating Northland jobs, strengthening regional economies and supporting a resilient, multi-source supply chain.
It’s important to take a broad view in considering the embodied impacts of building materials – not just on the climate, but also the local environment. Timber has a number of environmental impact issues that need to be managed and for which there doesn’t appear to be a clear industry strategy.
- Timber’s higher impacts in EPDs: Local manufacturers’ environmental product declarations (EPDs) largely show timber having greater effects than concrete on water depletion; embodied energy; particulate matter emissions; eco-toxicity; and soil quality. These impacts matter, especially when scaling the industry beyond its current extent.
- Wilding pines: The primary timber species in New Zealand, Pinus radiata, is the most recorded wilding tree species on the Department of Conservation’s 2024 weed list. Researchers suggest “a levy on economic uses of invasive species to offset costs of managing invasions, alongside stricter regulations to protect vulnerable ecosystems”.
- Biodiversity impacts: Monoculture plantations are inherently less diverse than native forests. A Scion report on biodiversity in plantations indicates that many species gravitate towards “native ecosystem remnants” within plantations – suggesting that prioritising commercial exotic timber plantations over native species afforestation does have negative biodiversity impacts. In contrast, quarries supplying materials to the concrete industry provide up to eight times their surface area in biodiversity compensation.
- Timber treatment and waste: Untreated radiata has a low natural durability. In order to compete against concrete in critical structural functions and/or with outdoors exposure, structural timber is heavily treated, sometimes with Chromated Copper Arsenate (CCA). CCA remains banned for residential use in the US, UK and EU. Landfilling such timber may store carbon, but the chemical burden (and risk of leaching) endures. There are numerous sources on the adverse effects of current treatment practices.
- Monoculture vulnerability: In Europe and the US, monocultures are failing and are being replaced with biodiverse native habitats or more resilient, multi-species plantations. These changes are not yet seen or even widely suggested in New Zealand, but we can’t pretend we don’t face the same challenges.
- New Zealand plantation industry practices: Recently, Forest Stewardship Council (FSC) experts have described certain New Zealand forestry practices as among the worst “they have seen anywhere”. Academics have suggested that significant regulatory improvement is required and existing rules are not always enforced. Rather than acknowledging the science and advancing environmental protection, we note that the beneficial effects of native forestry on steep slopes and erosion-prone land have been removed from the recently published Second Emissions Reduction Plan. Forest Owners’ Association data suggests only about 60% of New Zealand’s plantations remain certified as carbon neutral after deducting the two companies whose certification was suspended in the aftermath of the Gisborne disaster.
A better way – a level playing field
The concrete and cement industry is a strong advocate for neutral policy settings which establish a level playing field, so building materials can compete on their price and merits. This means factoring in the embodied emissions of products, but it should also include considering their wider externalities, including their impact on the environment.
Globally and locally, we’re making significant progress reducing the emissions intensity of concrete and cement, which has been acknowledged by the UN – and we are confident these will continue to play a central role. Timber of course also has a role to play, but this should be determined by markets, not by the preferences of politicians or policymakers.
We face a global poly-crisis – from climate change and water scarcity to pollution and biodiversity loss – all of which demand clear, balanced, evidence-based responses. And all of this forms the context for a Government trying to deliver a generational investment to fill our infrastructure gap.
And as we face more extreme weather events like fire and flooding, we need resilient construction materials.
It is vital we approach these challenges with openness, robust data and a willingness to acknowledge each material’s full lifecycle impacts. We again encourage constructive dialogue, underpinned by factual accuracy, so that stakeholders can reach informed decisions for the benefit of Aotearoa New Zealand and future generations.
