A breath of fresh air at Bradmill Yarraville

Creating a certified passive house — the international sustainable homes gold standard — is unattainably expensive for most buyers.

The cost of materials, expertise, and technology, much of which has to be imported, makes passive house building a bespoke exercise unsuited to scale building.

But a groundbreaking comparative study conducted at Frasers Property’s Life, Point Cook community in Melbourne’s west has identified the passive house inclusions which deliver the best “bang for buck”.

Those elements are now being offered as a mix of standard and upgrades in townhomes at Frasers Property’s Bradmill community in Yarraville and were also incorporated into the Brunswick and Co (now known as WeAreLiving Brunswick) apartment building in Brisbane.

The study saw two identical homes built side-by-side at Life, Point Cook, one a 6-Star “business as usual” house and the other adhering to international “Passivhaus” standards.

The pilot study, a first for an Australian volume builder, found that after one year of occupancy the passive house had consumed half as much energy as the BAU home.

In addition, air quality within the passive house was better, humidity was reduced and noise levels were significantly lower.

Kate Nason, Sustainability Manager, Development for Frasers Property said the study allowed each element within the passive house to be analysed for its effectiveness and what it delivered in terms of energy reduction benefits.

“We were able to look at the aspects of passive house design that delivered most effectively in terms of reducing energy consumption, without being cost prohibitive, and incorporate them into the townhomes we are delivering at Bradmill, and to aspects of the WeAreLiving Brunswick building,” she said.

As a result Bradmill is an all-electric community where solar panels, double glazing, better airtightness and top-of-the-range continuous thermal insulation is now standard.

Solar batteries, EV charging and balanced air filtration systems are available as upgrades.

The balanced filtration system is particularly groundbreaking, with its inclusion as a stand-alone customer upgrade package a first for a volume builder.

It removes dust, pollen and pollution from the air outside before it enters the home and filters allergens within the home. It allows air in the home to be “turned over” regularly without the need to open windows and lose the home’s heat or coolness.

The system is proving to be of particular interest for buyers who may have asthma or pet allergies in their family, as well as those who simply want to save money on heating and cooling bills. WeAreLiving Brunswick is an all-electric building with solar PV incorporating heat-resistant materials and better airtightness measures.

“The main focus was on reducing the energy bills of our customers, but that of course has the parallel benefit of being more sustainable,” Kate said. “And the other major benefit is improved quality of living. These homes are quieter, with pleasant temperatures that don’t require constant heating or cooling, and they have better air quality, which is particularly important in inner city locations.”

While some inclusions, such as solar PV, are a matter of installing hardware, the airtightness aspect involved holding expert-led workshops with building teams and contractors as well as design teams.

Airtightness refers to how well a building prevents the flow of air between interior and exterior. It reduces heating and cooling costs in all climates but is particularly impactful during periods of high and low temperatures.

It can be achieved at the design level through simplicity of building envelope and in the building process through careful sealing around windows and doors among other techniques and is then measured via a “blower door test” which uses pressure to determine the levels at which air is escaping a building.

“We spent a lot of time capacity building with our staff, builders and contractors, bringing in experts to help them achieve the airtightness we wanted from our residences,” Kate said. “Those are lessons that they’ll take with them to future projects.”

The Point Cook project saw Frasers Property become the first volume builder in Australia to create a passive house, a process which revealed both the possibilities and the constraints of delivering to a mass market.

With many of the products highly specialised and only available through importation, local supply and expertise is essential for the passive house model to become accessible at scale, but that doesn’t mean the model can’t be adapted for what’s possible now, Kate said.

“While we know that volume building to full passive house standard is not a realistic proposition right now, we’re confident we have delivered a practical and sustainable version that will be appealing to customers wanting to reduce their energy bills and improve their quality of life.”