How urban planners are creating ‘the hottest place on earth’ in Sydney’s west – packing McMansions with black roofs and no greenery – with experts saying temperatures can regularly hit 50 degrees

A leading urban planner has warned that a western Sydney suburb will become ‘the hottest place in the world’ within six months.

Sam Austin, who is currently NSW’s Young Planner of the Year, said residents of Marsden Park, about 50km north-west of the CBD, will soon be sweltering with temperatures of up to 50°C over the coming summer.

Mr Austin said several poor design choices made during the construction of developments in western Sydney meant residents were now living in dangerous urban heat islands where temperatures were 10 to 12 degrees hotter than the rest of Sydney.

Suburbs such as Marsden Park have helped create heat islands in the city that reach over 50C. What makes it so hot? Houses,” he explained in a video posted to social media.

“Especially these brand new, identical houses that are being built all over the country. Most of these houses have black roofs and a small garden with no room for a tree.

‘Street verges are too narrow for a mature tree. The roads are black asphalt, and this goes on for miles.

These factors combined create areas that can be more than 12°C hotter than neighboring suburbs. That’s right, the color of your roof can increase the heat by 12 degrees.’

An urban planner has warned that a western Sydney suburb is on the verge of becoming ‘the hottest place in the world’ within six months (Photo: Marsden Park construction)

Mr Austin ended his video with a stark warning to residents of Western Sydney.

“Western Sydney was the hottest place on Earth three years ago,” he said.

“It will happen again.”

Mr Austin is referring to when Penrith, about 55km west of the CBD, hit a record-breaking 48.9°C on 4 January 2020 and was officially the hottest place on Earth.

The staggering temperature was recorded as the state was ravaged by bushfires, with central Sydney reaching 35°C on the same day.

Canberra also reached record highs, with a January afternoon temperature of 43°C.

More than three years later, extreme heat remains a major problem for residents of western Sydney, who are already experiencing temperatures up to 10 to 12 degrees hotter than those living in the eastern suburbs.

Dozens of concerned Sydneysiders shared their concerns, and one asked, “Why are there no trees?”

‘Because developers are too cheap to install greenery and allow greenery, less green more houses’, replied another.

Penrith in western Sydney was the hottest place on Earth on January 4, 2020, reaching 48.9°C

Penrith residents cool off in the Nepean River after temperatures soared above 40°C in January 2020 during a horror bushfire season

‘I used to take my child to a GP in Marsden Park. About three years ago I was driving it home from the doctor in the summer and the car’s temperature gauge read 50°C,” someone said.

‘Gregory Hills in (south west) Sydney is the same. The new construction on Menangle has white roofs. But still no additional trees planted,” wrote another.

Austin said the combination of black roofs, miles of asphalt and a lack of greenery had created the urban “heat islands” in western Sydney.

He told news.com.au that while trees and grass can absorb the sun’s heat, fake grass and “impermeable surfaces like concrete and roofing… spit it back out.”

NSW’s Young Planner of the Year said black roofs were purely for “decorative choice” but were in fact at least six degrees hotter than a white roof.

The urban planner said the lack of vegetation meant there was less water in the atmosphere, which in turn hindered efforts to cool the concrete environment.

More than three years later, extreme heat remains a major problem for residents of western Sydney, who are already experiencing temperatures up to eight to 10 degrees hotter than those living in the eastern suburbs (Photo: Marsden Park construction)

Austin said the combination of black roofs, miles of asphalt and a lack of greenery had created dangerous “urban heat islands” in western Sydney (Photo: Marsden Park)

Mr Austin said those living in western Sydney have traditionally been residents who are more socio-economically disadvantaged than those in other parts of the city.

He said these “vulnerable” people would face higher energy bills as a result of trying to stay cool during the coming summer months.

Construction on identical developments to the one at Marsden Park began after the previous Liberal government announced specific ‘urban release areas’.

The sprawling developments in western Sydney have seemingly provided the NSW government with a short-term solution to the growing housing crisis.

Mr Austin said there are several low-cost solutions to mitigate conditions in the ‘heat islands’, including more vegetation, white rather than black roofs and ensuring there is enough space to plant mature trees that can provide shade to assure.

Sobering models from the Australia Institute in 2022 revealed that Western Sydney is on track to experience five times as many extreme heat days a year if nothing is done to curb emissions.

The report found that in a high emissions scenario, Penrith could endure up to 58 days or two months of extreme heat per year.