The passive house first became a thing in 1991 when Dr. Feist determined a way to design a home or building that did not require heating or cooling interventions, such as ducted heating and air conditioning. It’s hard to believe that we could do away with these appliances through smart design and maximising the use of existing energy within a space such as human body heat, and energy from existing appliances such as lighting, and even your TV!
It’s not passive, and it’s not just for houses. The name comes from the German “Passivhaus”. It is passive only in the sense that the building envelope does most of the work to maintain comfortable temperatures, without active input from the occupant/s. “Haus” is the direct translation of “building”, encompassing everything from single and multi-residential buildings to schools, hospitals and offices.
Passive house starts at design. It relies on 5 design principles and performance criteria that deliver an efficient and comfortable space for the life of the building.
5 key design principles for a passive house are
1. Appropriate levels of insulation of ceilings wall and floors keeping the heat in when it’s cold and keeping it out when it is hot.
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2. No air leakages or, airtightness. Drafts bring unwanted hot or cold air.
3. No thermal bridges. Thermal bridges allow heat to escape from the inside to the outside.
4. High performance windows double or even triple glazed so that the ambient temperature is maintained inside the property, and consideration of orientation to maximise the sun in winter and shade in summer. That ideal temperature ranges between 20 and 26 degrees celsius.
5. Heat recovery ventilation which pumps fresh air into the property for good air quality which facilitates good health, and avoidance of mould and condensation
Learn more about passive house in this short video: Passive house explained in 90 seconds
While passive house does start with design, there are many ways to retrofit your existing home for much improved energy efficiency, comfort and health. We will cover this off in future blogs but let’s start by talking about why we should be focused on it and the reasons are plain to see and feel – increasing energy costs, climate change and negative impact on health.
Increasing energy costs
Wholesale electricity prices have increased by 141% since last year. Australia exports most of its fossil fuels including coal and gas, and oil. As prices are increasing globally and transport costs are on a serious upward trajectory, energy prices must increase accordingly. The Russia/Ukraine war also threatens global energy supply chains.
Extreme weather events experienced in Australia have increased energy usage and are predicted to continue to do so due to climate change.
Read more from UNSW about what is fuelling the increased costs of energy (pardon the pun!)
As defined by the UN, climate change refers to long-term shifts in temperatures and weather patterns. These shifts may be natural, but since the 1800s, human activities have been the main driver of climate change, primarily due to the burning of fossil fuels (like coal, oil and gas), which produces heat-trapping gases.
The potential effects of global climate change include more frequent wildfires, longer periods of drought in some regions, and an increase in the duration and intensity of tropical storms, which some parts of Australia have experienced to the extreme these past few of years.
This topic resonates with an increasing number of Australians (judging by the latest Federal election results). “Changes to the climate system have occurred and are likely to continue”. Everyone on this planet has a role to play in reducing consumption overall – of products, and services such as energy supply” according to CSIRO. Have a read of this CSIRO study on climate change in Australia.
Negative impact on health
Air quality has a huge impact on our health. Be it excessive heat or cold, pollution, or mould, all can have a profound impact on the way we feel and, especially on our elderly and vulnerable communities.
“As in other countries the population of Australia is ageing. In 2017 about 15% of the Australian population consisted of people aged 65 years or above and in the next 40 years the proportion is expected to grow to 22% of the total population. Ageing in your own home for as long and comfortably as possible is the preference of the majority of older Australians and the focus of government strategies. Home modifications and assistive devices may be required to accommodate the occupants as they age and particularly when they become frail. However, modifications to aid thermal comfort are not always considered”.
So, hopefully we have piqued your interest to learn more about passive housing principles and how Enviroflex can provide excellent solutions to drive energy efficiency and reduced energy costs, contribute to a positive impact on climate change and improve your overall health, comfort and wellbeing.