What Is a Passive House? Australian Design, Cost & Standards
A passive house (Passivhaus) is a home built to a strict airtightness, insulation and ventilation standard so it needs almost no active heating or cooling — using 80–90% less heating and cooling energy than a conventional Australian build and typically rating 9–10 stars on NatHERS. Passive house design costs roughly 8–15% more to build. Here's how it works, what passive homes cost in Australia, and where the standard fits alongside the NCC 2022 7-star minimum.
Passive House vs NatHERS 7 stars
| NatHERS 7 stars | Passive House | |
|---|---|---|
| Status | Legal minimum (NCC 2022) | Voluntary international standard |
| Heating/cooling energy | ~50 MJ/m²/yr (climate-dependent) | ≤ 15 kWh/m²/yr (~54 MJ for heating and cooling combined cap) |
| Air-tightness | Not measured | ≤ 0.6 ACH @ 50 Pa (blower-door verified) |
| Ventilation | Natural / exhaust fans | MVHR (heat-recovery ventilation) |
| Verification | Plans-based modelling | On-site testing + certification |
| Build cost uplift | +0.5%–3% over 6 stars | +5%–15% over NCC minimum |
The 5 Passive House principles
- 1. Continuous high-performance insulation
- 2. Thermal-bridge-free detailing
- 3. Air-tight building envelope
- 4. High-performance windows (triple glazing common)
- 5. Mechanical ventilation with heat recovery (MVHR)
What Passive House owners report
- • Heating/cooling bills 80–90% lower
- • Constant 20–25°C indoors year-round
- • Filtered fresh air, lower pollen and PM2.5
- • Near-silent indoor environment
- • Resilience during heatwaves and grid outages
Targeting Passive House? Start with a NatHERS-accredited assessor
Many of our assessors specialise in high-performance and Passive House-style builds — they'll model your design in NatHERS first, flag any star-rating issues, and refer you to a certified Passive House Designer if needed.