The relentless sprawl into Sydney’s west is far from creating an Australian suburban dream, more an Australian nightmare, an academic says.
Poorly designed, crammed-in homes in new developments west of the city are reaching hazardous temperatures, Sebastian Pfautsch says.
Sydney's urban sprawl Photo: top images -Image copyright: Nearmap, 2020, bottom Image copyright: S. Pfautsch, 2020
Pfautsch is an associate professor of urban studies at Western Sydney University and says the urban sprawl to suburbs in the city's outer west could be a ticking time bomb for the health of hundreds of thousands of people, with some new suburbs experiencing heat 15 degrees hotter than other parts of the city.
He took six readings in the Western Suburbs last summer that recorded more than 50 degrees celcius.
“Which is half way to boiling point. In some places of the world, particularly Scandinavia, you may use that as a sauna temperature.”
But people have to roast in these temperatures for hours, he says.
The prediction is for longer lasting heatwaves in this part of the Sydney basin, he says, only making the problem worse where there could consecutive days of extreme heat.
More important still are the night time temperatures, he says.
“This is where our body would normally recover from the extreme stress during the day but if night time temperatures are 30 degrees and more your body can not recover.”
Two or three hot nights in a row and admissions to ER go up exponentially particularly in the older age groups, Pfautsch says.
A typical new building in Western Sydney becomes uncomfortably hot inside when the outside temperature is 32 degrees if it is not cooled, he says.
“It’s stuffy, it’s getting really hot because the materials that you use radiate heat inside the buildings.
“So, if you have a tin roof that’s made from a dark grey or even black colour bond then you can have roof temperatures of 70-75 degrees and that heat is radiating into your house.
“Also, you have a lot of window space because modern houses do want to have the natural light if you have all the additional sunshine coming through your single glazed windows you add another proportion of heat to your house.
“And then you have the problem that there is no shade on the outside, there’s no green infrastructure, there’s no trees because during the development of these suburbs you have basically eradicated the existing green infrastructure.”
Air-conditioning is often not an option for people in Sydney’s west, he says.
“People who settle out west often are renting, they don’t have the means to buy their own home, there’s a huge proportion up to 40 percent actually renting and out of that proportion you again have a very large chunk of people that do not have the disposable income to actually switch the air conditioning unit on.”
The NSW state government is planning for 800,000 more people to come to Sydney in the coming decades and the only place for homes to go is in the west, but the resulting homes being built are hot boxes, Pfautsch says.
“What you see out west are big houses on small blocks with no green infrastructure around them, with black roofs with single glazing. Maybe with a PV solar on top of it, maybe not.
“And then you end up with the suburbs that we are seeing where the local government basically allows developers to create these heat suburbs, or heat boxes for the individual houses that become the norm and everyone thinks this is the way to go.”
This is not the Australian dream, it is the Australian nightmare, he says.
“We are really creating conditions that are hazardous for the next decades, where you have this new build environment that is brand new now you will not tear that down for at least the next 40 years.
“So, we are locked in with this kind of development to deal with in decades where it is only going to be hotter.”
And the suburbs within which these new builds sit have heat radiation built in to them, he says.
A second wave of heat comes from hot air vented from air conditioning and cars, trains and unshaded roads radiating absorbed heat through the night - something known as the urban heat island effect.
“Throughout the world urban areas can be 15 degrees hotter during the night than surrounding vegetated areas.”
There are both easy and more difficult solutions to this problem, he says.
“An easy example would be don’t have black roofs anymore, In Los Angeles the policy makers were able to ban black roofs and prescribe light-coloured roofs more than ten years ago.
“It’s possible, it is very easy to do, you just have to do it.”
Double or triple glazing should be standard as it is in most European countries.
“Things like that that are not impacting hugely on your budget to build a house.”
Good thermal insulation and a move away from open plan will also help, he says.
“Open plan means you have to cool your whole floor because there is no more compartmentalisation between rooms you just have one open space and it takes a lot of energy to cool down.”
More difficult solutions will require more stick and less carrot, he says.
“Not to build to the maximum extent on their blocks and allow more open space for strategic planting.”
Ideally planning for the future should be based on a concept known as heat smart density, he says.
“Moving away from a single dwelling for each individual family and each individual house more into town houses and apartments and starting to build up into towers 25-30 storeys high.
“You are not having houses covering all the space but you have one very dense centre embedded in parklands which are the centre of community.”
Without this kind of planning approach there is no chance of building resilience into suburbs in hot parts of the world such as Sydney, he says.
And air conditioning is not the answer, he says, the grid in Sydney being unable to cope with cooling every class room let alone every home.
One possible solution to this is decentralising electricity grids, he says, where autonomous provision and storage of electricity becomes the norm.
“We have no chance of greening cities if we continue with business as usual building these flat and wide new suburbs with materials that are heat absorbent.”
