Building Science in Action: A Deep Dive into Three Melbourne Passive House Projects
At Carland Constructions, we don't just build sustainable homes—we build high-performance machines. To ensure these homes perform exactly as promised, we rely on the Passive House Planning Package (PHPP). This is a rigorous energy modelling tool that calculates performance based on actual physics rather than the guesses used in standard building ratings.
We have analysed the data from three of our key Melbourne projects: Forrest, Champion, and Pigeon. While they share a similar scientific DNA, their unique site conditions and component selections show exactly how building physics works in the real world.
Every project begins in the PHPP. Unlike standard Australian rating schemes that use generic climate data, the PHPP uses specific latitude and altitude coordinates for Melbourne. We model every square centimetre of the thermal envelope, accounting for:
Heat Loss: Calculating specific U-values for walls, roofs, and floors.
Thermal Bridging: Identifying and eliminating highways for heat at every junction.
Solar Gains: Precisely placing and sizing windows to capture winter sun while using shading to block summer heat.
The Foundation: Slab vs. Subfloor
A major differentiator in performance modelling is how the home meets the ground. At Carland Constructions, we adapt the engineering to the specific site requirements:
The Slab Advantage:Pigeon Certified Passive House (Yarraville) used a high-performance slab on grade foundation. In these builds, the slab acts as a thermal battery, absorbing passive solar gain and slowly releasing it to maintain stable temperatures.
The Subfloor Strategy:Champion Certified Passive House (Williamstown) and Forrest Certified Passive House (Spotswood) utilize suspended timber subfloors. Modelling these requires a ventilated crawl space calculation. To prevent heat loss through the floor, we install heavy-duty insulation—like R5.0 Pink Batts at Champion—within the joists to create a complete thermal break from the earth.
The Window Specs: Comparing Triple Glazing Performance
Windows are usually the weakest part of a thermal envelope. While all three projects use triple glazing, we selected frame materials to suit each project's specific performance and aesthetic goals.
ProjectWindow Frame
Champion (Williamstown)Logikwin 68 Aluclad Centre-of-glass U-values as low as 0.53 W/(m²K).
Forrest (Spotswood)Koemmerling C70 uPVCTypically modelled with a glazing U-value of 0.75 W/(m²K).
Pigeon (Yarraville)High-Performance uPVC Modelled for extreme efficiency, reaching a project-wide average of 0.98 W/(m²K).
The Constant: Zehnder ComfoAir Q350 HRV
While the foundations and windows varied, the lungs of these homes remained constant. All three projects utilize the Zehnder ComfoAir Q350 Mechanical Ventilation with Heat Recovery (HRV) system.
In an airtight home, controlled ventilation is non-negotiable. The Q350 is modelled to:
Recover over 80% of heat from extracted stale air and transfer it to incoming fresh air.
Filter out pollutants like dust and pollen—essential for air quality in Melbourne's Inner West.
Eliminate the condensation conundrum that causes mould in traditional builds by constantly moving air.
Airtightness: The Proof in the Pudding
The beauty of Passive House is that performance is quantifiable. A standard new home in Australia might have an airtightness of 15.0 air changes per hour (ACH50), but as a Certified Passive House builder Melbourne specialist, our projects achieved elite results:
Champion Certified Passive House (Williamstown): Achieved 0.4 ACH50.
Forrest Certified Passive House (Spotswood): Hit an impressive 0.41 ACH50.
Pigeon Certified Passive House (Yarraville): Reached a remarkable 0.24 ACH50, setting a new benchmark for precision construction in Melbourne.
These results translate directly to comfort and savings. All three homes modelled with an annual heating demand at or below 14 kWh/(m²a), meaning they require roughly 90% less energy to heat than a standard build.
Are you ready to move beyond the 7-star minimum and build a home that actually performs? Reach out to the team at Carland Constructions to speak with the high performance homes Melbourne experts today.