Residents of Western Sydney now routinely dread the baking days of summer, when temperatures can soar into the 40s in some districts – heat of 44 degrees has been recorded at Badgerys Creek, 43.9 at Penrith Lakes, 43.8 at Richmond Airbase. Days when it’s too hot to let the kids play outside, too hot to walk a few blocks to visit a friend, too hot to ride a bike to the shops or work in the yard.
Decades of poor planning have led to this heat sink and to date there are no government regulations to force developers to adopt any meaningful heat mitigation measures, says Professor Sebastian Pfautsch, co-lead of the Urban Transformations Research Centre at Western Sydney University.
“We’re sleepwalking into the next super El Nino,” he adds, noting extremely hot weather has been predicted for the coming summer by the World Meteorological Association and Australia’s Bureau of Meteorology.
With climate change projected to drive ever-higher temperatures, Western Sydney’s heat sink is affecting the lives of millions of people. “We allowed it to happen,” Pfautsch says, adding the worst housing developments have been “moon-scaped”: flattened, with trees and creek lines removed to allow for the easy construction of big houses on small blocks with hardly any room for shade trees or even vegetable gardens.
The current push for increased housing supply has undermined any impetus for heat mitigation, he adds, and updates to the residential elements of the National Construction Code have been paused for years.
As little as $12,000 per dwelling could provide houses able to cope far better with hotter summers but, along with heat-reflective light-coloured roofing and effective tree cover, this seems to have become a difficult ask.
“It’s completely ludicrous,” Pfautsch says. “Our building quality is going down when we are going into the decades to come where we have to deal with longer and hotter summers.”
The NSW government has set a target of 40 per cent average tree canopy cover across Greater Sydney to provide shade and comfort. Yet Pfautsch says his research suggests that with the current rate, regions in Western Sydney including suburbs like Box Hill, Kellyville, Schofields and Marsden Park, will have 9 per cent cover by 2040.
He has also analysed Australian Bureau of Statistics data from the last census and found the five-bedroom homes on small blocks on these spreading developments house an average of 3.2 people.
“It’s just crazy,” he says. “It’s not fit for purpose. The families that buy these homes don’t need five bedrooms, but they can’t get smaller homes. This model has a 20 per cent profit margin costed in and the development industry doesn’t need to change it because the demand is so high.”
For its part, earlier this year the NSW government awarded millions of dollars for modest greening projects across the state, including about $5 million in Western Sydney (two projects of $94,000 and $203,000 for Fairfield, for instance, one of the most heat-vulnerable areas).
A new Climate Change and Natural Hazards State Environmental Planning Policy (SEPP) and Urban Heat Policy statement is in the works – the consultation period concluded in March, and the Department of Planning, Housing and Infrastructure is now “considering feedback”.
Building regulations were boosted in 2023 with the idea that builders are now required to follow BASIX 7-star thermal performance ratings, designed to keep new homes more energy-efficient and more comfortable on hotter days.
Yet Pfautsch says these rules do nothing for the environment outside the house, and new developments can continue with “very little green, zero deep soil, zero shade trees”, and he is not sure how much interior comfort the regulations will ensure on days of extreme heat.
Still, Pfautsch’s co-director at WSU’s Urban Transformations Research Centre, Professor of Planning Nicky Morrison says the conversation has shifted from awareness of the problem to coordination and funding of solutions at scale.
“There is the recognition that heat really is intersecting with housing,” she says, adding that the enabling infrastructure of heat mitigation, including cooling tree canopies, cooling corridors, and cooling roof materials will entail significant upstream costs. “It’s hard to break that ‘business as usual’ model,” she says. “There are tried and tested developers who aren’t wanting to do it, and they’ll fight hard on the viability of all this, but I think it’s come into mainstream discussions so we do have some levers.”
This includes state and local government planning policies now in the works, but policy alone isn’t enough, she adds, it’s important to make sure change is implemented on the ground.
It’s not only the new communities that need more thoughtful planning for heat mitigation, says Emma Bacon, CEO of Sweltering Cities, the NGO she founded in 2020. The broad sweep of existing Western Sydney suburbia requires support to deal with oppressive days of high temperatures, she says.
Intense pressure from developers on councils and state governments has kept heat mitigation requirements to a minimum, she adds, and Western Sydney needs a planning system that ensures sufficient tree cover and heat minimising roofs among other elements. She and her colleagues have been taking about the potential heat problems of dark roofs for more than six years, she says.
“The pressure is between good design and sustainability,” she says. “We’re finding that design and planning is being driven by the market, rather than asking what type of communities we want to live in, what type of nature we want around us. Are we going to say it’s acceptable for us that there will be places where it will be dangerously hot to leave the house for potentially days or weeks at a time?”
Developers are building the cheapest possible houses, Bacon adds, which are expensive to live in – with the subsequent power and healthcare costs are borne by the owners.
While the state government is largely responsible for planning controls on housing, Western Sydney councils are “by far the most advanced of any in the country on heat policy”, she says, led by the Western Sydney Regional Organisation of Councils and the council collaboration Resilient Sydney, though much of the guidance is not legally enforceable.
Bacon celebrates even the smaller wins, such as convincing the NSW government to help fund bus shelters and bus seats in some of Western Sydney’s hottest suburbs. Standing next to a bare bus-sign pole on a baking street with no shade on a hot day is a painful exercise, and can actually be dangerous.
Fairfield, for instance, has extremely high “heat vulnerability”, and bus stops adjacent to childcare or aged car facilities should be sheltered from the sun, Bacon says.
“We pushed the state government to commit funding to put more bus shelters in Western Sydney, which they did a couple of months ago,” she says. “That was done by community members volunteering, advocating, talking to local politicians, talking to local councils, supported by us, and we actually got the state government to commit to funding that they’d said no to for years.”