Champion Passive House, Williamstown

What does a truly comfortable home actually mean?

You have probably heard a lot about sustainability and energy efficiency lately. These words are everywhere, but in practice the building industry takes a fragmented approach, bolting on individual green features without ever considering how they work together as a system. A solar panel here. A double-glazed window there. Insulation that meets the minimum. The result is homes that fall short of their real potential for comfort, health, and durability. The only way to build a genuinely sustainable home in Melbourne is to build to the Passive House standard. That is what we believe, and this is how we proved it for the second time.

The clients came to us with a clear brief. They were not familiar with Passive House, and that was fine. They wanted a comfortable, healthy, and resilient home for their two children, one that would not cost a fortune to run. They wanted a sanctuary separated from the outdoors, but one where they could connect to the outside whenever they chose, through generous triple-glazed aluclad windows and doors. They wanted a home that would be a place to raise a family, not just a building to live in.

Those goals led us, together with Altereco Design, to a certified Passive House. The conversation happened early in the design process, which is the only way this works. Plan for a high-performing home from the start and you achieve real savings and avoid costly compromises later. Leave it until the drawings are finalised and you are retrofitting performance into a design that was never built to deliver it.

This is Carland Constructions' second certified Passive House project.

What is a certified Passive House, and what does Plus mean?

Passive House Classic requires a building to meet airtightness, heating demand, cooling demand, and primary energy thresholds, then prove them through physical testing and third-party certification.

Passive House Plus goes further. It adds a minimum renewable energy generation requirement relative to the building's footprint area. The building must not only consume very little energy, it must generate enough on-site to offset a meaningful portion of its total demand.

The Champion Passive House achieved Passive House Plus certification, certified by Detail Green in December 2024. It is one of a small number of certified Passive House Plus projects in Victoria.

How we built it

The Champion Passive House is a single-storey timber-framed construction on a suspended floor over a ventilated crawl space.

The floor.

R5 Pink Batt insulation (200mm of glasswool) between 200mm floor joists, 19mm particle board on top, building wrap membrane below. U-value 0.258 W/(m²K). Annual ground heat losses: 668 kWh. An uninsulated suspended floor in a standard Melbourne home runs three to four times that heat loss every heating season.

The walls.

140mm timber stud frame, R3.5 Polysorb batts in the primary frame, 45mm service cavity insulated with R0.8, Pro Clima building wrap as the continuous airtight layer, 10mm plasterboard internally. Wall U-value: 0.294 W/(m²K). Total wall area: 223.1 m². Annual transmission losses: 1,562 kWh. Every cable and pipe runs inside the service cavity, inside the membrane, so the airtight layer is never penetrated by trades.

The roof.

CSR Bradford R7.0 batts (290mm) throughout all three roof assemblies, trusses at 600mm centres. U-value consistent at 0.155 W/(m²K) across the entire ceiling plane. Total roof area: 187.9 m². Annual transmission losses: 692 kWh. No weak spots, no compromised sections. R7 throughout.

Airtightness.

Depressurisation: 0.40 ACH50. Pressurisation: 0.39 ACH50. Certified result: 0.39 ACH50. Marginally better than the Forrest Passive House. By this project our detailing, sequencing, and trade briefing process had tightened up considerably. It shows in the number.

Windows.

LogikWin 68 aluminium-pine-meranti composite frames with PressGlass Silverstar triple glazing. Primary glazing Ug-value: 0.58 W/(m²K), g-value: 0.53. Overall installed Uw: 0.975 W/(m²K). Total window area: 45.2 m². Heating season solar gains (1,221 kWh) exceed transmission losses (1,049 kWh), meaning the windows are net contributors to heating the home in winter.

Mechanical ventilation.

MVHR system, 80.2% heat recovery efficiency. Supply air change rate: 0.40 ACH. Annual ventilation heat losses: 353 kWh (2.2 kWh/m²a). Automatic summer bypass controlled by temperature difference, contributing to a cooling demand of just 3.0 kWh/(m²a). Williamstown sits within Hobsons Bay, where hospital admissions for asthma run around 20% above the Australian average (Inner West Air Quality Community Reference Group, 2020). Every cubic metre of air entering this home is filtered before it reaches a living space. For a family with two children in Melbourne's inner west, that is not a detail. It is the point.

What the clients said

"We couldn't be happier with our experience building with Matt and his incredible team. From start to finish, their professionalism and expertise in Passive House construction were second to none. Matt's passion for this building methodology shines through in every aspect of our home, and the final result has exceeded all our expectations. The performance of our Passive House is simply unparalleled.

One of the things we appreciated most was the level of care and communication throughout the build. The team held regular fortnightly onsite meetings to ensure we were always up to speed, and they were consistently friendly, approachable, and available to answer any questions we had. We genuinely felt like they were an extension of our family.

The site was always kept immaculately clean and tidy, and it was clear that they took great pride in their work. They also showed incredible respect to our neighbours, which meant a lot to us. Visiting the site always felt like coming home early. We had zero issues along the way, which is a testament to their organisation, skill, and dedication."

Airtightness: 0.39 ACH50

Heating demand: 13.8 kWh/(m²a)

Heating load: 11.0 W/m²

Cooling demand: 3.0 kWh/(m²a)

Primary Energy Renewable demand: 36.4 kWh/(m²a)

Renewable energy generation relative to footprint: 53 kWh/(m²a)

Frequency of excessive humidity: 0%

Passive House Plus: Yes