So what is ‘Passive House’?
If you are at all interested in sustainable building, it is highly likely you have heard of ‘Passive House’.
Passive House (also known as Passivhaus where it originated in Germany) is an international method or technical standard of designing and construction a building to achieve a very high level of energy-efficiency, with little or no heating or cooling required. It is not to be confused with Solar Passive Design Principles (which includes orientation/natural ventilation/insulation/shading/thermal mass etc.) although most of these principles can still play a part in the overall design.
It is not an architectural style, but more concerned with the building science of how the building is put together and how it performs.
Here’s a super simple 90 second explanation for you:
So, the basic 5 elements of a Passive house are:
1 Well insulated building envelope (This is to walls, roof and floor – so the building is like an esky.)
2 Airtight envelope (If you have gaps in your building, it is like trying to have a warm bath without the plug in – you have to keep filling it up with more hot water! We want to avoid this.)
3 Great windows (In our climate, high-quality and well sealed double-glazed windows should suffice, sometimes triple-glazing is preferable.)
4 Eliminate Thermal Bridges (This is one of the most ignored issues with current buildings – especially with steel/aluminium framing that conducts heat/cold through the building fabric. Construction details are important here.)
5 Controlled Ventilation (An air-tight building still needs ventilation – but it must be controlled – not leaky drafts and air gaps all over the place. You can still open in windows in a Passive House, but also a low-energy and efficient mechanical ventilation system is required to ensure fresh air circulates throughout the building.)
Passive House aims for a comfortable indoor air temperature of 20 degrees celsius all year round, and uses 60% to 90% less energy than a 6 star house. It is a life-cycle costing approach – so although it will cost more up front in construction costs, it will have huge reductions in the cost of heating/cooling building for over 60 years (not to mention the amount of carbon emissions saved).
It is worthwhile to note that energy to heat and cool is still the MOST energy consumed over a building’s lifetime – much more so than the embodied energy of the construction materials.
As a member of the Australian Passive House Association, I’m off to the Australian Passive House conference next week – I can’t wait to learn from some of the world’s leading experts in this field and apply this knowledge to my projects.
Have you heard of Passive House? Do you have questions about it? I’d love to know your thoughts in the comments below, don’t be shy now!
Talina Edwards Architecture is a Ballarat-based studio, with a passion for sustainable design, green buildings and healthy homes. Click here to ensure you won’t miss out on our elemental design news!