Case study: As an environmental consultant Chris Buntine deals with advanced sustainability approaches every day in the commercial space. Now, with the renovation project he and partner, Sun Buntine are undertaking in Hampton in Melbourne’s south east, he’s road-testing regenerative design and construction principles on their new family home.
The project began when they purchased a century-old California bungalow that many would consider a prime candidate for a knock-down rebuild. But the Buntines looked at the home and saw embodied carbon that deserved to be stewarded to the greatest extent possible.
Instead of building on a blank canvas, the “Biophilic Bungalow” project aims to achieve Passive House standard, integrates biophilic design and implements biodiversity-friendly design within the constraints of the existing structure and site conditions.
The Living Building Challenge Core Certification and LBC Energy petal requirements are also being used to guide decisions, and certification may eventually be pursued.
An overarching ambition is to use the renovation process to stimulate a wider conversation in the property community about creating homes that are energy positive, carbon neutral, water resilient, zero waste, healthy and nature positive.
It’s about showing how even in our existing urban fabric we can be re-connecting people with nature, weaving links within communities and dissolving the perceived barrier between human zones and the natural habitat of native plants and animals. Blue-banded bees and busy family lives can co-exist, where humans create spaces that are inclusive of the wider web of existence.
At its root, regenerative development aims to create multiple layers of value for a place and for the life of that place, Buntine explains. It means contributing to the health and vitality of that place and the systems including ecology, water, energy and materials which it is part of.
“A project, whether it is a building, a piece of infrastructure or an open space, is regenerative when it builds the capacity of the wider community of life to renew, evolve and thrive. If a project looks great but degrades the quality of its surrounding environment or a place far away, then it is degenerative.
“One sustainable project is a nice achievement, but what is so much better is a regenerative project that creates ripples of positive contribution that builds stronger more connected communities, enriches ecological systems, transforms materials supply chains and brings life to Country.”
Circular principles in practice
Buntine says retained materials will include the majority off the timber structure, which consists largely of Oregon Pine imported from the US in the early 1900s. Where interior walls are being left in place, much of the existing lath and plaster will also be retained and provide significant thermal mass.
Because there had been extremely limited retrofitting or upgrades to building services or appliances over the home’s 100 year lifespan, Buntine says no equipment or appliances could be retained.
“The gas appliances had no future application in an all-electric house, the kitchen appliances were 40 years old and in poor condition, the single split systems was at the end of its useful life, the wiring and plumbing systems were well behind what would be needed to meet code and there was no insulation, aside from some loosely placed batts in the attic.
“While we have embraced the concept of circularity in our project, we have also had to be realistic about the poor build quality of some aspects of an older single-family home, and the complexity and cost of trying to retain and repurpose some existing materials and equipment.”
There were also materials contaminated by lead paint or asbestos that could not be refurbished or re-used.
“Deconstruction isn’t a process we embrace much in Australia, but it is the only way forward if we want to reduce waste to landfill, and to respect and value the uniqueness and history of existing materials.”
Materials and products that are excess to project requirements yet still have some life in them were donated for rehoming through Facebook Marketplace.
“It has been amazing to us to see the level of interest in materials we have removed from the house that would otherwise have ended up in landfill including a gazebo, electric fireplace, kitchen cabinets, garage door hinges, bricks, garden edging, shade screens, bricks, corrugated iron and an entire set of bathroom fittings and fixtures,” Buntine says.
“Other (non-useable) materials have been separated onsite [for recycling] to facilitate diversion from landfill including concrete, wood, metal, carpet and vegetation.”
Buntine says that in parts of the US, it is no longer legal to demolish a building, so projects like his would need to hire a “deconstruction contractor”.
“Deconstruction isn’t a process we embrace much in Australia, but it is the only way forward if we want to reduce waste to landfill, and to respect and value the uniqueness and history of existing materials.”
“It takes no more than a quick Google search to find that the demolition is a far more favoured practice in Australia than deconstruction.”
While deconstruction is labour intensive and comes with potential hazards such as asbestos, without it, Buntine says the building industry will “struggle to become anything close to circular.”
“(It) will need government regulation to make it ubiquitous and well implemented,” he says.
Energy and water
For energy, the Buntine’s goal is to invest in an onsite renewable energy system that combines generation, storage and energy management. This will also provide “far greater energy resilience and autonomy.”
“We won’t pursue the same level of autonomy for our water system for the simple reason that small scale decentralised water treatment systems are complex and expensive to purchase and maintain. Instead, we will focus on a water resilient building and landscape, with onsite storage and plumbing to allow use of recycled water for toilet flushing, and diversion of grey water to landscape if needed.”
Designing with nature in mind
To achieve the goal of biodiversity-friendly design, the Buntines held a workshop to talk about biodiversity in their backyard, bringing together members of the local community and sustainability practitioners.
This helped to shift our collective focus from human wellbeing to ecological thriving, Buntine says.
“In our neighbourhood, single family housing can be generalised as a big house with some grass and a pool. Despite the biodiversity crisis, single family home construction and renovation projects are required to do practically nothing to address our endangered flora and fauna.
“This isn’t an abstract crisis, as the loss of insect populations and small bush birds in our area, is in plain view for those paying attention.”
How the system fails on biodiversity
Because there was no change of use involved in the project, there wasn’t a requirement to go through statutory planning approvals, which meant requirements for a Statement of Environmental Effects was not triggered.
Biophilic Bungalow only has to meet the Victorian residential development provisions and the building code. Buntine notes that neither of these require any actions to preserve or enhance site biodiversity.
In Victoria the SEE process is the key method for assessing a proposal against the requirements of legislation including the Environmental Protection and Biodiversity Conservation Act, Australia’s cornerstone federal nature protection legislation.
Biophilic Bungalow only has to meet the Victorian residential development provisions and the building code. Buntine notes that neither of these require any actions to preserve or enhance site biodiversity.
“Having this important biodiversity conversation in our backyard created awareness, understanding and agency for us all. There was so much we could do whether we had just a balcony or a large acreage.”
It was also confronting for the sustainability professionals, he says. There was a realisation “our education and training had failed us.”
“We knew far too little about our Indigenous ecosystem, it was humbling. But there was joy in talking about the tawny frogmouth, the brown butterfly and the superb blue fairy wren and how we could encourage them to come and make this backyard their home.
He said they learned some simple ideas such as ensuring landscaping includes dense prickly endemic bushes that can provide small birds a place of refuge.
Expanding thinking and growing community networks
There’s been some broader professional reflections too. Buntine says that while he’s worked on many large building development projects, there’s not been one yet in which the team asked the question, “what species can this project help regenerate?”
Engaging with the neighbours as part of the regenerative project journey has also created a much larger sense of community for the Buntines.
“By sharing our aspirations and inviting their contribution we have already built friendships with many of the people along our street, and we are still a year away from moving in.”
For the approach to catch on and become mainstream, Buntine says investing in high ambition sustainability and regeneration must create value in the market.
“The opportunity for me to share the story of our house project in ways that might influence others to take a similar journey, is one of ways we hope to make a regenerative impact.”
Reflections on regenerative practice
Regeneration is inherently a complex concept, just as nature is complex. Lack of full understanding should not be a barrier, however.
“It is so important in our time that we get busy with regeneration at the level we do understand it, rather than getting sidetracked chasing more perfect definitions,” Buntine says.
“There is still so much we still don’t understand about how to harmonise human development with healthy and resilient ecological systems.”
“I like to visualise the ripples created from a pebble landing in a pond, with those ripples symbolising a small but ever-expanding positive impact we can all have on the larger system.”
