Opinion: It’s the small things

We have come a considerable way in our understanding of what ‘sustainable design’ means in 2024.  

As an industry, we have spent the last five years aggressively upskilling ourselves in terminology like embodied and upfront carbon, net zero, sequestration, emissions and all things kgCO2e/m2. We’ve been hit with these all at once – and demystifying this new language¹ has been critical for us to engage and advance our practices; and to contribute towards building better, more resilient cities. Wherever you sit on the continuum in comprehending the science of it all, we should all by now (at least) be in strong agreement that our climate is changing, and unless we change how we fundamentally approach our design processes, we’re not changing at all.

There’s a bit at play on a macro level: Aotearoa New Zealand has a net zero target by 2050, and the building and construction sector contributes to about 20% of NZ’s carbon emissions through energy and materials used in buildings². As designers, and specifically in my role as an architect, I have often felt powerless to truly shift this dial. But I’ve come to the realisation that incremental efforts matter – and in turn, will slowly and eventually contribute to the overhaul of business-as-usual.

In my role as project architect on 90 Devonport Road – which upon completion, will be NZ’s largest hybrid mass timber office building – there was a series of workflows the entire team undertook to ensure ‘success’. In this context, success for us was the ability to employ a hybrid mass timber structure, which put simply, cut the building’s upfront carbon by almost 50%³. To be clear, this was success was due to collective effort – where all parties⁴  (client, consultants, contractors, tenant) unanimously came together to collaborate and ideate. But for the purposes of this piece, I’ve attempted to distil these into three key principles that stood out to me: timing, simplicity, and agility.

Timing 

The opportunity to influence the extent of carbon reduction was the greatest at the beginning of the design process⁵. The willingness and enthusiasm to explore options and make decisions remained fluid and malleable in the early stages of design, after which the window of opportunity exponentially decreased. At this early stage, the team was willing to test and iterate ideas which opened prospects to explore building with new and innovative materials, minimise waste, price in any unknowns, and move forward. For us, this enabled exploring envelope and structural design schemes that eventually facilitated the use of a hybrid mass timber structure.

In addition, the willingness to measure at the outset was important. Put simply, we weren’t going to make any progress without understanding the breadth of what we were trying to achieve. Measurement took on two parts – first, establishing the ‘benchmark’ or ‘base case’, and then following up with the ‘improved’ position. The willingness to measure enabled a form of transparency – and outlined the full extent of efforts needed to make meaningful carbon savings.  

Lastly, timing of procurement and early contractor engagement played a crucial role. Engaging early enabled the team to take up opportunities around refining buildability, explore supply options, while also rationalising the design to enable efficient construction methodologies.

Simplicity 

At the time of design, it’s fair to say that there were a few unknowns when it came to designing and constructing mass timber buildings of this scale. Sitting at 8-storeys, 90 Devonport didn’t have any national precedents that reached this height in a commercial typology (others have been built, but they were either much lower in height or were for a different use which would change the structural and fire engineering approach entirely). In this context, designing to support the use of a mass timber with ambitious spans relied on a simplicity of geometry. 

We retained this simplicity through various aspects by focussing on rationalised spans and modules. Structural bays were selected to suit the material and reduce waste – which meant that status quo positions around commercial-grade column spans and floor to floor heights were interrogated and challenged. We also advocated for familiar and repeatable selections where possible (for example, façade selections), while mitigating any complex geometries. In short, our hope was that we could offset any unknowns by proposing complementary systems that brought familiarity and/or flexibility. 

Agility 

At the core, achieving a low carbon outcome was the attitude. The team was fully committed to communicating and remaining agile. Proposing, testing, reacting, and adjusting – and being able to do so quickly – was critical. We ran concurrent schemes, measured various outputs, and tested alternatives as required. We also attempted to remain ‘non-precious’ at large – as it was easy and tempting to be otherwise.

As I use this opportunity to reflect on the design and construction process to date, I’m aware that this is only one perspective of many in the journey towards delivering this specific low-carbon outcome.

It’s fair to say that this was a truly collective effort, and a fine balance of skills, determination and circumstance. But all this to say that the team went into this process with a certain level of optimism – and while tackling those macro goals can sometimes feel slightly out of reach, it’s often the small, incremental efforts that contribute to bigger change.