As the climate crisis escalates, the Sustainability Summit positions itself as a vital forum for reimagining how our cities and communities are designed, built and governed. Bringing together leaders from architecture, construction, policy, planning and engineering, the Summit explores bold ideas and practical interventions shaping the future of the built environment.

At the 2025 edition of the Summit, the subject of regenerative architecture set the stage for a candid discussion on how architects, urban planners, and developers can go beyond carbon neutrality to design buildings that contribute positively to the environment. Moderated by Architecture & Design Editor Branko Miletic, the panel featuring Liam Wallis from HIP V HYPE, John McIldowie, Practice Director, McIldowie Partners Architects, Alison Potter, Design Principal, HDR, and Dr Matthias Irger, National Head of Sustainability, COX Architecture, revealed through the lens of biomimicry, carbon-positive materials, living buildings and nature-based design, how regenerative thinking can redefine the relationship between the built and natural environments.

How is regenerative different from sustainable or net zero?

Reflecting on her own journey to regenerative practice, HDR’s Alison Potter speaks about how humans are innately connected to nature, and how nature has the ability to not only sustain but also restore and rejuvenate. A book on regenerative design written by noted American architect and landscape architecture educator John Tillman Lyle in the 1990s frames design as a process that restores, renews and revitalises its own sources of energy and materials. That idea, she explains, marks a clear shift away from linear thinking and towards cyclical systems that can sustain themselves through regeneration.

For award-winning architect John McIldowie, regenerative design aligns closely with architecture’s primary objective to make the world a better place. While architects, he says, do it all the time, they either don’t think about it in the context of the environment or adopt a very linear approach. “Regenerative design is about leaving the place better than what it was before.”

Emphasising the need for action to restore the natural environment, HIP V HYPE founder Liam Wallis reflects how cities, for all their benefits in terms of lifting people out of poverty and improving living standards, have also, in the process, destroyed our natural systems and environments.

Sharing a deeply personal experience of rafting down Tasmania’s Franklin River – a “journey through an ecosystem” as he describes it, he observes, “We don't spend enough time as humans to experience and learn from nature, and understand the importance of protecting it, which would go a long way to healing so many of our issues today.”

According to Dr Matthias Erga, sustainability focuses on the status quo, keeping things the same, net zero is also a balance, but regenerative design tries to leave a legacy through positive impacts. Looking beyond integrating nature, he says one should also consider co-benefits, particularly focusing on community outcomes that will stand the test of time.

Sustainability_Summit_2025_Biomimicry (4).jpg — *Architecture and Design Editor Branko Miletic*

Biomimicry in practice

Dr Erga observes that biomimicry can be applied at multiple scales, from materials inspired by the lotus leaf to create surfaces that don’t absorb dirt, to building forms that are shaped by natural elements, such as the Quadracci Pavilion by Santiago Calatrava in Milwaukee, USA. However, in the context of the climate and biodiversity crisis, there can be more impact from studying processes and focussing on improving them. Living buildings, he says, try to have a positive impact, and also integrate and improve the ecology of a site.

There's something about learning from nature, observes Potter, drawing on her personal experience at the Eden Project by Grimshaw in Cornwall, UK, which she describes as one of her “all-time favourite examples of biomimicry”. Since the quarry was still being mined during the design phase, the constantly shifting landscape led the architects to take inspiration from soap bubbles and their ability to naturally form geometries against each other, to create the biome structures at the site.

Spending time on site at the start of a project and understanding the place from the perspective of nature – that’s how you connect biomimicry to the design thinking, she adds.

Engineers are much better at considering natural systems than architects, says McIldowie, recalling the time he came across enormous wind turbine blades at an industrial estate in Geelong and noticed how the blades had very fine serrated edges, similar to an owl's wings – the intent being to create nearly silent wind turbines.

Wallis concurs, saying that there’s considerable work being done at an engineering level in the industrial design space, such as reef support infrastructure based on the lattice-type structure of existing reefs, and can be produced locally and installed in the middle of the ocean with minimal skills.

This is the kind of thinking that needs to be applied in the building space to get meaningful outcomes, he says. “It's incumbent on us as professionals in the built environment to find opportunities to carve out the ability to test new ideas at smaller scales, low-risk settings.” This can be achieved through collaborations with young engineers and industrial designers and bring that learning meaningfully into projects in a way that genuinely enables innovation.

Risk, innovation and scaling to more meaningful adoption

However, Wallis says risk aversion is a major roadblock to innovation. “It's not even money half the time.”

This can be overcome through small-scale testing to trial new ideas without excessive risk. A company in Melbourne, for instance, works in the net zero carbon concrete space and has started testing their product in a small way in landscape architecture. Another product that has come out of the University of Melbourne is clay-activated concrete, which has now been scaled up for testing in infrastructure projects.

However, such innovations, he says, face structural and risk-based barriers to scaling into more meaningful adoption, including entrenched supply chains and commercial inertia.

By testing things out without being driven by fear or complacency, we can demonstrate what's possible, responds Potter. “Hope is an action,” says Potter. “I think regenerative design is about planting a seed, demonstrating what's possible and creating hope.” During times of crisis, she explains, nature finds a way to regenerate and create something new, and that’s something to learn from.

Regenerative design is about doing things differently, and is, therefore, often misunderstood as risky, comments Dr Erga. Be it a building, a precinct or a city, regenerative projects are intrinsically more resilient with lower risk. Overcoming this hurdle demands a complete shift in mindset, he adds.

Designing with Country: Regenerative architecture built on Indigenous knowledge

The conversation shifts to the panellists’ experience with integrating Indigenous knowledge into regenerative design to help restore land and ecological systems.

Sharing how the Indigenous people collect emu eggs during the appearance of the Emu constellation, McIldowie says it’s an excellent example of regenerative thinking embedded in culture as it ensures the sustainable harvesting of a food source.

“There's so much that we can learn from Traditional Owners. To me, the value or the opportunity is about listening and designing a process – not a building – that genuinely engages with Traditional Owners in a process of co-design. It's not designer and stakeholder; it's shared ownership of the design.”

McIldowie’s firm is currently working on a few projects where this approach is being applied, with Indigenous groups guiding regenerative planting, local material sourcing, and even reef restoration beyond the site boundary, driving deep engagement and value.

“It's a process of listening and collaborating with them, and a co-design process is the starting point,” he says.

Sustainability_Summit_2025_Biomimicry (3).jpg

Barriers to regenerative design

Integrating nature, Dr Erga says, is probably the cheapest way to get very impactful regenerative outcomes because there are many different co-benefits.

However, applying regenerative design principles depends on the client and their values in terms of their own goals for sustainability, community engagement and legacy creation. Embodied carbon is a hard sell, for instance, because there is no requirement to reduce it, and is seen as extra cost.

Reframing the conversation around the building’s life cycle, materiality and circularity could help with convincing clients about the value proposition. “There's value in something that's existing, and the more value you can capture of that in theory, the cheaper should be your building, and certainly your environmental footprint is greatly reduced,” he explains.

A post-occupancy evaluation of a building could help shift perception by providing clear visibility into productivity, health and wellbeing gains, be it an office, school or hospital.

Measuring success in regenerative design

Measurement is very layered, and it changes over time, says Potter. While there are tools to provide structure based on metrics, in practice, it’s more about the stories that come through in terms of human and social benefits and getting clarity on tangible outcomes.

Ideally, it’s important to capture knowledge about building systems and approaches during the development process, and share it between project teams, says Wallis. However, this is not done effectively because of time and cost constraints, making it difficult to leverage learnings for the next project.

Even failures should be considered when evaluating performance because they provide insights for course correction in future projects, says Dr Erga.

Getting feedback from people using the building can provide great learning outcomes, which can be fed into the briefing processes of future projects, ensuring effective knowledge transfer to different design teams so that they are not starting from scratch, adds Wallis.

Regenerative design is something for the occupants to learn about, says McIldowie, explaining that buildings and products have a role in communicating their value to people over time. At a recent project, the landscape architect designed a green roof with a specific planting scheme to capture endangered native butterflies without a habitat, who happen to fly overhead as part of their travel path. Measurement of the impact, in this case, provides a mechanism for the occupants to learn about the world that they're living in, rather than a tool to decide if the project is good or bad.

What could make a project regenerative?

Green roofs, says McIldowie, can bring nature to any project immediately, which can also replace the environment on the concrete roof. By reducing the use of concrete, a green roof also delivers biodiversity benefits.

For Potter, it’s about designing from first principles because every site is unique, and also exploring potential so that there’s no spending later on for missed opportunities. Focussing on improvement at every stage of the project can lead to better outcomes but it requires a mind shift, she adds.

“I would settle on doing more with less,” says Dr Erga. And it’s not just about using less materials – it’s about choosing right and understanding the materials being put in the project better by asking questions about the supply chain, recyclability, recycled content and sustainable sourcing among others.

“For me, it's spending the time to understand why early,” says Wallis. Well-designed tools like the Living Building Challenge create a framework where there's a strong understanding of why any given project is doing what it's doing. This gets to the heart of regenerative practices.

And when the project is done right, there’s pride, ownership, and potential. “It's really important to understand why you're doing what you're doing, and to be able to transfer that through the entire project procurement cycle,” he explains.

This panel was sponsored by our partners, SAS International and SUPAWOOD Architectural Lining Systems.

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Main image: (L-R) Branko Miletic, Liam Wallis, John McIldowie, Alison Potter and Dr Matthias Irger

Architecture & Design Team

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