The Passivhaus standard, a design and construction methodology that promotes internal comfort and energy efficiency, was formalised over a quarter of a century ago and is based on research into past and present high-performance structures.

In Europe, a Passivhaus building consumes up to 90% less heating and cooling energy than typical buildings (Passivhaus Institute, 2017).

Passivhaus buildings must meet a number of fundamental performance criteria to be eligible for certification, with the three key criteria being:

• a minimised demand for heating and cooling

• an air-tight thermal envelope, and

• significantly reduces whole building energy use.

A Passivhaus is typically certified upon build completion, with the airtightness test, commissioning report and photographic evidence verifying build quality, though there is no time limit. In its purest technical terms, Passivhaus is defined by an independent research institute for Passivhaus, the Passivhaus Institut, as a building meeting the criteria in Table 1 below:

Extracts from Environmental Design Guide 89 CP – May 2017 Passivhaus: The pathway to low energy buildings in Australasia. Clare Parry, Australian Passive House Association.

5 Basic Principles of Passive House

• A continuous layer of thermal insulation.

• Avoid thermal bridge effects.

• High-performing windows suited to climate.

• An airtight envelope.

• Mechanical ventilation system with heat recovery.

The ultimate aim of building to the Passive House standard is not necessarily the final certification but rather achieving exactly what the standard promises to deliver: a comfortable, high-quality, healthy building that costs very little to run.

Advantages of a Passive House building.

Healthy home.

The one aspect of the Passivhaus methodology that gained my interest was the health values of these buildings. The airtight layer and the mechanical ventilation system filter the air to a very high level and create a full fresh air exchange every three hours. Imagine living in a house with constant filtered fresh air flowing—with no dust (dust mites), bad odours, pollution, and if you suffer from hay fever, no pollens!

Airflow is increased in bedrooms, providing fresh air as you sleep and removing the CO2 buildup that can make you feel groggy when you wake up.

Minimal to zero energy costs.

In Australia, there is a lower difference between indoor and outdoor temperatures compared to, say, Northern Europe. Therefore, energy costs can be reduced by 90% quite easily, and the additional 10% can be created by renewables (e.g., PV cells), therefore creating a zero-energy-consuming home.

Internal comfort.

If you ever get the opportunity to visit a Passivhaus building do it!! It is very hard to describe the internal comfort levels compared to the real-life experience of the space. All rooms are kept to the same temperature and the clean air is just so lovely, I never want to leave once I’m in.