Climate-friendly buildings without unintended consequences
Emissions reduction is no longer an option for New Zealand.
The passing of the Zero Carbon Act is a monumental step for us to achieve our commitments under the Paris agreement and show leadership globally by legally committing to net zero carbon by 2050.
There’s a lot of debate in the media about how we’ll achieve our targets – and beyond the first two five-yearly emissions budgets, much is pinned on future technological advances.
A big focus currently is reducing the ‘embodied emissions’ of our built environment, which account for about 20% of New Zealand’s total national emissions.
Embodied emissions are those generated from making and transporting materials used and in the construction activities – though they do not factor in emissions from materials at the end of a structure’s life.
Let’s be clear, materials like steel contribute a large chunk of a building’s embodied emissions. So, are these materials going to impede our journey to zero-carbon and kill the planet (and house prices), or are they part of the solution?
Firstly, the Climate Change Commission’s first two five-year emissions budgets will focus on reducing operational emissions, principally from transport but also the operational energy used in our buildings (which is not factored into embodied emissions).
This will also give high-energy, high-carbon emitting industries like steelmaking, the time horizon to significantly improve their operational efficiency, adopt new low-emission technologies and chart their path along the net zero-carbon transition.
Secondly, the transition will require significant investment in renewable energy, particularly new wind and geothermal generation, along with mass transit systems and in creating a resilient built environment – all of which require large quantities of steel and concrete.
So, before we write off the very products New Zealand will depend upon for a successful transition, New Zealand needs to reflect upon past periods of rapid change in New Zealand and how government, policy and the market have delivered costly, obtuse outcomes for New Zealand.
One of the most important lessons is the reforms of the 1980’s and 90’s that gave New Zealand’s housing construction a performance-based building code, untreated timber and the weathertightness debacle that we are still resolving today. This has cost hundreds of thousands of New Zealanders their life savings and along with their homes and their health.
These market-led reforms were designed to deliver simpler, more affordable solutions. But instead facilitated the introduction of untreated timber in house framing, a rise in monolithic claddings construction with new materials which were sealed with miraculous sealants replacing traditional flashings - all at a time when skills training was in turmoil.
In 2019 MBIE commenced a significant programme of regulatory reform and many of the conditions of the 1990’s continue to manifest themselves in a 21st century guise.
We have significant shortages of construction skills, contractors are looking offshore for cheaper material solutions, and in some cases completely fabricated dwellings designed and built for Asian environments which differ significantly from New Zealand’s harsh UV, challenging climate and shaky ground.
In the built environment the global warnings are there. The 2011 Christchurch earthquakes and the 2016 Kaikoura event drove changes to design codes and construction methods which result in more resilient structures. Recent tragic fire events in the UK have seen the UK government ban use of flammable materials on the external walls of buildings taller than 18 meters.
The Ministry of Business Innovation and Employment in 2019 has provided a deliberation limiting use of flammable materials to less than 10 meters in residential structures.
We need materials like steel and will continue to need them. Steel is strong, resilient and lightweight. It can be recycled infinitely without any degradation of quality and easily harvested from a demolition site for re-use as is, repurposing or recycling.
Actions that focus only on one part of a product or building’s life cycle may have the unintended consequence of shifting environmental problems from one part of the product’s life cycle to another.
Its high strength to weight ratio means less is needed to get the same outcome and it is pre-manufactured in quality-controlled factories to precision specifications so there is no waste on site.
Steelmaking in New Zealand contributes to just 2.2% of our total carbon emissions, much lower than other industries and comes with Environmental Product Declarations unlike much of what we import.
Ultimately, the industry is excited to embark on this new period of reform to achieve New Zealand’s carbon emission targets learning from the unintended consequences of past reforms.
We need to use the first two budget periods of the Climate Change commission to ensure that future policy is informed by robust data on the life cycle of structural building materials, available skills and the stewardship of key materials upon which our future relies.
Legislation that focuses only on one part of a product’s life cycle may have the unintended consequence of shifting environmental problems from one part of a building or product’s life cycle to another.
Nick Collins is CEO of Metals New Zealand and part of the Sustainable Steel Council