f you’re building a home in Australia, you’ve likely come across NatHERS.
It’s the standard used to measure the thermal performance of residential buildings —
and for most projects, it’s a required part of compliance.
But there’s another approach that’s gaining attention: Passive House.
While both aim to improve comfort and energy performance,
they are fundamentally different in how they work —
and in what they deliver.
What is Passive House?
Passive House is a performance-based building standard that focuses on reducing energy demand to an absolute minimum —
while maintaining consistent indoor comfort.
Unlike NatHERS, it doesn’t rely on a star rating.
Instead, it sets strict, measurable targets for:
- energy use
- airtightness
- indoor air quality
- thermal comfort
These are verified through detailed modelling and on-site testing.
👉 For a full overview, see our Passive House guide.
Key differences between Passive House and NatHERS
Approach
NatHERS is a rating system.
It evaluates how a building performs and assigns a score.
Passive House is a standard.
It defines exactly how a building must perform — and verifies it.
Performance vs compliance
NatHERS is primarily used for compliance.
A building needs to meet a minimum star rating to be approved.
Passive House goes beyond minimum requirements.
It focuses on achieving consistent performance in real conditions.
Energy modelling
Both use modelling, but in different ways.
NatHERS modelling is used to generate a rating.
Passive House modelling (via PHPP) is used to design, test, and refine the building —
ensuring it meets strict performance targets before construction begins.
Airtightness and testing
NatHERS does not require airtightness testing.
Passive House requires verified airtightness,
typically achieving a maximum of 0.6 air changes per hour (ACH50).
This has a major impact on comfort and energy efficiency.
Ventilation
NatHERS does not require mechanical ventilation.
Passive House includes continuous mechanical ventilation with heat recovery (MVHR),
providing fresh, filtered air at all times.
Comfort
Both aim to improve comfort.
But Passive House is designed to eliminate:
- temperature swings
- drafts
- uneven heating and cooling
The result is a more stable and predictable indoor environment.
Can a home be both NatHERS and Passive House?
Yes.
In Australia, most Passive House projects are still required
to demonstrate compliance with NatHERS or BASIX.
However, Passive House goes far beyond these requirements.
In many cases, a Passive House will naturally achieve a high NatHERS rating —
but the reverse is not always true.
Which one should you choose?
For most homeowners, NatHERS is not a choice —
it’s a requirement.
Passive House is a decision.
You might consider Passive House if you:
- want consistent comfort year-round
- are concerned about rising energy costs
- value indoor air quality
- are building a high-performance or architect-designed home
It’s not necessary for every project.
But it is one of the most reliable ways
to achieve what many homes aim for — but don’t consistently deliver.
Final thoughts
NatHERS sets the baseline for building performance in Australia.
Passive House raises that baseline —
by focusing on what the building actually delivers in everyday use.
The difference is not just in ratings or targets,
but in how the home feels to live in.
Learn more about how Passive House works in Australia
