Go online, and you'll find many social media posts complaining about Australia’s cold houses in the winter.
And it’s not just a trivial gripe either.
The World Health Organisation reported that 81 percent of Australian houses have temperatures below the optimum 16 to 18 degrees Celsius (64 Fahrenheit) minimum.
The cause lies in a mix of factors.
RMIT University’s Nicola Willand from the School of Property said Australian homes tend to be uninsulated, draughty, and fitted with inefficient heating systems.
“This means that warmth dissipates quickly once the heating is switched off. Air movement between heated areas and the colder walls and windows makes people feel uncomfortable, making heating very ineffective and expensive,” she said in a statement.
“Australians build some of the largest homes in the world, and bigger areas translate into higher energy demand.
“Even though new homes are more energy efficient, central heating in these large homes can be too expensive if householders are burdened with high mortgage payments. Restricting heating to one or two rooms is difficult, as heating control is limited, with many homes having a maximum of two zones to switch on/off.”
Ms. Willand said most Australians accept that their homes will be chilly in winter.
“Many people are unaware of the health risks associated with cold homes [and] the risks of cold indoor air for respiratory and heart health, infections and mould,” she said.
“For renters, minimum rental standards in Victoria call for one heater in the living area.
“This leaves bedrooms cold and at risk of mould, or tenants must use expensive portable electric heaters.”
In New South Wales, rental homes only need to be fitted with heaters in the cooler areas.
“The Nationwide House Energy Rating Scheme (NatHERS), which governs the home energy star ratings for new dwellings, assumes that living room heaters are switched off between midnight and 7 a.m.,” Ms. Willand said.
“Unless homes are well insulated and draught-proofed, the warmth will slowly dissipate, resulting in cold kitchens and living areas in the morning.”
NatHERS also assumes a thermostat setting of 15 degrees in bedrooms from midnight to 7 a.m., which again falls below world guidelines.
“By contrast, energy efficiency ratings in other countries will assume heating in all rooms and at all hours of the day and night,” Ms. Willand said.
“That ‘chill in the morning’ is certainly a widely shared experience in Australia—but it shouldn’t be.”
The Australian Building Code has also been lacking.
Australia was once a nation with very affordable electricity, so it was not in a position to factor in structural approaches to building warmth.
Fast forward to the current era, and Australia’s power prices have soared, making it expensive to warm up in winter.
Professor Ralph Horne from RMIT said Australians tend to focus on natural disasters like bushfires, droughts, and floods, neglecting energy efficiency and heating.
“As far back as 2005, research comparing Australian cities to those overseas found housing in compatible climate zones in North America and Europe was 55 percent more efficient for heating and cooling energy than minimum standard housing in Australia,” Mr. Horne said.
“An implicit reliance on cheap energy has now become increasingly challenged by the need to respond to climate change and the rise in energy poverty.”
Experts recommend keeping homes warmer in winter by sealing gaps and cracks, adding or improving insulation and installing double-glazed windows.
