Summer in Australia seems to bite harder each year. Adelaide set a record maximum temperature for the nation’s capital cities of 46.6°C last week and there have been extreme heatwaves around Australia. The challenge to remain at a comfortable temperature in our homes is unprecedented.
Early European design influence used shade and ventilation strategies. The wrap-around veranda and classical Queenslander are examples that respond to the harsh Australian summer. This design response was typically paired with behaviour like children playing under the lawn sprinkler, or sleeping under the veranda to catch the evening breeze.
The rise of air conditioning has moved us away from climatically and culturally sensitive ways to deliver comfort during extremes. For many, the press of a button provides superior and controllable comfort. This has led to high energy and energy infrastructure costs, especially when used in peak heatwave periods. It also increases carbon dioxide emissions, which are driving climate change.
Design for climate
These homes represent a modern reinterpretation of design for climate, based on the science of energy and materials. Such homes are a marriage of passive solar design, building material characteristics and technologies to reduce energy use and provide energy on site.
In this context, recently published research conducted in South Australia asks: are we unlearning coping strategies used to actively manage our thermal comfort? We interviewed householders of the Lochiel Park green village in Adelaide to explore individuals’ housing histories to understand the changing relationship between the occupant, the building and the resultant energy use.
Lochiel Park was Australia’s first large-scale attempt to create homes that use near net zero energy in a net zero-carbon precinct. The homes are rated a minimum 7.5 NatHERS stars. They have double glazing, ceiling fans, solar water heaters, solar PV, energy-efficient appliances and energy-feedback displays. All of these features were, and remain, well above the requirements of building regulations.University of South Australia, Author provided
The research revealed occupants had used a wide range of practices to adapt to extremes in their previous houses. They discussed strategies like sleeping downstairs, in well-vented hallways, or outside under the veranda where it cooled down more quickly at night. Typical behavioural responses included active management of homes like closing curtains and blinds to shut out the sun, fixing temporary shade-screens or opening the house to gully breezes each evening.
The introduction of the air conditioner changed buildings and lifestyles. Single-room air conditioners redefined strategies: instead of sleeping outdoors, residents might drag mattresses into the lounge room. No longer did the local swimming pool look as inviting. As one resident put it: “… I’m not going to go outside in the heat to get in the pool.”
External shading or heavy drapes were no longer seen as necessary. Venetian blinds and other lightweight window furnishings became popular. Active operation by opening and closing windows, doors and curtains became less important.
Authors: Trivess Moore, Lecturer, RMIT University