The built environment accounts for up to 20 percent of Aotearoa New Zealand’s total emissions and a response is critical in the shift towards a low carbon economy. RDT Pacific carbon hero, Cameron Spence shares valuable insights on how we can turn this around.

Cameron Spence knows how to take the complex out of carbon. He is part of the RDT Pacific team of sustainability experts leading change in New Zealand’s sustainable construction practices.

While Cameron admits carbon can be a hot potato, and New Zealand has got some ground to cover to reduce emissions, he is confident a low carbon future is in our sights. In this interview, he shares ways the construction industry can reduce carbon, why a shift of mindset can reap unexpected rewards, and how RDT Pacific’s carbon services have made a significant impact in driving sustainable building practices.

 

How does the New Zealand construction sector affect carbon emissions?

The short answer is the New Zealand built environment contributes to 13 to 20 percent of all emissions. So, the construction sector is a significant contributor to New Zealand’s overall carbon footprint.

 

What factors contribute to carbon emissions and what needs to be addressed?

Buildings make up a big segment of construction, and they emit carbon throughout their life cycle. A building with a typical life cycle of 60 years has two contributing factors which make up the building’s total carbon emissions – embodied carbon and operational carbon. Together they make up the whole-of-life carbon footprint of a building. It’s vital we understand the differences between them and their impact on climate change, and how we handle them differently.

Although we are most familiar with operational carbon, there is a growing awareness of embodied carbon and its impact. Embodied carbon refers to the carbon emissions associated with building materials throughout their lifecycle – from raw material extraction, production, and transportation to construction and disposal at the end of the building’s life. These activities are influenced during design and occur over a shorter period compared to the operational phase of the building.

In contrast, operational carbon, primarily from the building’s energy consumption, spans the majority of the building’s life cycle, occurring from the first day of occupation until it closes. Operational carbon currently accounts for most of the carbon emissions associated with a building’s life cycle. However, as our buildings become more energy efficient, and the energy grid becomes cleaner, embodied carbon will gradually account for a larger percentage of the total carbon footprint. Embodied carbon is a major contributing factor to emissions, but until recently it has been overlooked, and not measured in projects. This renewed focus on embodied carbon is a response and an acceptance of how immediate the threat of the climate crisis really is. It is necessary we measure both forms of carbon to get the total picture of a project’s impact. Choices made during design have a huge impact on both the embodied carbon and the longer learn operational carbon.

 

What are our biggest obstacles to reaching net zero carbon and how do we respond?

The biggest challenge for New Zealand in achieving net-zero emissions in the built environment is continuing to reduce operational carbon in our buildings while intensifying efforts to address the embodied carbon from construction, manufacturing and waste (which currently account for 50 percent of all waste generated in New Zealand).

We need to change as an industry, and we have a big opportunity to adopt carbon reduction measures that will also translate into efficiencies. We can influence change through education, and by working collaboratively in the sustainability space, we can overcome an obstacle for many – net zero carbon. There are challenges in terms of cost, availability of materials and construction practices, but as our focus and legislation changes, the market will respond. Materials will be adapted to demand for low carbon, and they will become more widely available, which we are already seeing with concrete.

 

How do we build a low carbon future for New Zealand?

We cannot take any steps towards building a low carbon future in New Zealand until we measure the carbon in our building or project – whether it is new or existing. We have to understand where the carbon is coming from, what materials are associated and the operational impacts. Data collection is the starting point.

With new buildings, we can measure embodied carbon for a standard reference building, alongside a fresh design that accounts for different choices with lower carbon content. For existing buildings, adaptive reuse and taking advantage of the existing carbon already built into the building is a critical part of a low carbon future. Once we understand where the carbon is coming from and what the hotspots are, then we can focus on reducing and mitigating the impact on the environment.

For operations, we must continue to decarbonise by eliminating fossil fuels to improve the energy efficiency in our buildings. For construction, the reuse of existing structures and materials must always be considered first to avoid additional embodied impacts. By measuring to best practice guidelines and being mindful, we are reducing carbon emissions and strengthening our assets.

 

How has RDT Pacific made a difference in this space?

RDT Pacific has undertaken several impactful projects that highlight our commitment to reducing carbon emissions in the built environment. For instance, alongside our Green Star projects, we recently completed a Life Cycle Assessment (LCA) for a project, focusing on measuring the reduced impacts during the operation phase through energy-efficient design, while also achieving a 10% reduction in embodied carbon. This project not only helped our client meet sustainability targets but also demonstrated the tangible benefits of integrating carbon reduction strategies early in the design process. In another project, we conducted an embodied carbon assessment on an existing building, enabling our client to understand the environmental advantages of refurbishing and renovating rather than opting for new construction. This assessment provided critical insights, showing that repurposing existing structures can significantly lower the overall carbon footprint.

 

What innovation is happening in the move to lower carbon construction in New Zealand?

I don’t have the most amazing or jaw-dropping answer, but what I find interesting about the innovation happening in terms of carbon and low carbon building is how things have come full circle. By reducing carbon, we are turning back to traditional practices, building techniques and natural materials like timber for construction and building.

This is also happening in the operation of buildings. Reducing carbon emissions has encouraged a focus on combining passive design techniques with technology, such as building management systems, to maximise savings. There is a renewed focus on passive heating and cooling, natural ventilation and rainwater harvesting.

 

What is the most valuable advice you can share to reduce carbon?

• Understand your asset. My biggest piece of advice to anyone is to make sure you measure your carbon and understand your asset.
• Construct building for longevity and reuse. We have to reduce, but we can go beyond that by constructing our buildings for longevity. Think beyond the building’s lifecycle in terms of its end of life as well. We need to try to design and build our buildings for reuse and deconstruction to avoid unnecessary emissions.
• Focus on the targets and outcomes. To avoid further irreversible environmental damage, we must prioritize achieving the goal of a zero-carbon Aotearoa by 2050. Beyond environmental benefits, low-carbon buildings offer additional advantages, including cost savings and healthier, more productive environments for New Zealanders.
• Do not be afraid of carbon. Carbon can be overcomplicated sometimes, but it can be really simple. It can be understood by anyone, and it is a meaningful conversation in any area of the design or construction process or building operation.

 

What drives your passion for reducing carbon?

My New Zealand childhood is a big inspiration. I have a deep love for this country and its culture, and a respect for the natural environment. I have seen on a smaller scale from my hometown of Blenheim what the misuse of our environment can lead to, and how destructive that can be.

The irresponsible activities of humans can result in real world and unnatural impacts. Carbon is a larger part of that, and we are already starting to see the impacts from years of misuse. It has now become physical, and it is very real. The good news is, we are seeing changes in the construction sector and we know how we need to respond and that we must keep influencing the market and the wider sector for this to happen.

Cameron Spence is part of a team of qualified sustainability advisory experts at RDT Pacific who are passionate about making Aotearoa New Zealand a better place. They are expert advisors who can measure your carbon, advise on best practices and manage projects to achieve sustainable building ratings.

 

 

Useful links

The Carbon Footprint of New Zealand’s Built Environment – thinkstep Australasia

A Net Zero Carbon Road Map for Aotearoa’s Buildings – New Zealand Green Building Council (NZGBC)

A Practical Guide to Upfront Carbon Reductions – Green Building Council Australia and NZGBC

Closing the Gap – Hidden emissions and untapped potential of buildings to reduce costs and deliver for carbon budgets – NZGBC

Aotearoa New Zealand’s first emissions reduction plan – Building and construction