The call for a ‘complete ban’ on popular home details is rocking neighbourhoods

Scorching temperatures across much of Australia this month have reignited calls for a “total ban” on black and dark roofs.

Seas of black and dark gray roofs are an extremely common sight in new developments in capital cities such as Sydney and Melbourne, but there have been growing calls in recent years to buck the popular trend that has taken hold over the past two decades.

“Almost every roof in western Sydney is black,” city planner Samuel Austin told news.com.au earlier this year.

“Fifteen or so years ago, having a dark colored roof became really popular. They look stylish and modern, so people loved them. The problem is that this is a 150 square meter area sitting in the sun all day attracting and absorbing large amounts of heat.

Experts have long warned that the urban heat island effect, in which some pockets experience significantly higher temperatures than surrounding areas and cool more slowly at night, will only worsen as the climate warms.

The mercury in parts of Sydney and Melbourne hit 40C last week, prompting heatwave warnings and power cuts affecting thousands of homes.

The Bureau of Meteorology and CSIRO have warned that Australia will face hotter temperatures and reduced rainfall in the coming decades.

The most recent biennial The state of the climate The report, published in October, found Australia’s climate warmed by an average of 1.51C since records began in 1910.

“Australia’s warmest year on record was 2019, and eight of the nine warmest years on record have occurred since 2013,” the report said.

“The record warm year of 2019 had 40 days of extremely hot average temperatures nationally (those in the warmest 1 percent of days for each month), about three times as many extreme heat days than any other year before 2000. Also in 2019, there were 33 days when national average daily maximum temperatures exceeded 39C, a higher number than seen in the 59 years since 1960 to 2018 combined.â€

Janine Strachan, chief executive of the Insulation Council of Australia and New Zealand (ICANZ), said the report should be a wake-up call to state and federal governments, planning authorities and industry, which have delayed reforms to thermal efficiency. standards in the face of financial difficulties affecting the construction sector.

“We need to recognize that the homes of the future that need to be built now are more resilient to climate change,” she said.

Strachan backed a “complete ban” on dark roofs in particular, which should be “seen as a stop-gap going forward if states really want to take their urban development seriously”, especially in the hottest parts of southeast.

In January, South Australia became the first state to take action, announcing that dark roofs would be eliminated from all future phases of Playford Alive, a major 500-hectare housing development in Adelaide’s northern suburbs.

A report by Seed Consulting, which heat mapped Adelaide’s northern suburbs, found that houses with light-coloured roofs were 4.3 degrees Celsius cooler on an average day than houses with dark roofs.

Urban planning expert Professor Sebastian Pfautsch from Western Sydney University has led calls for state governments to ban dark roofs.

“The decision to ban dark roofs should be replicated in Victoria and New South Wales, where developers and consumers continue to choose materials that amplify urban heat,” Prof Pfautsch said earlier this year.

“In a warming area, this development puts lives at risk. During a heat wave, when all these dark-roofed suburbs will be running their air conditioning systems, high demand increases the risk of power outages. And when the air conditioning goes off, the residents will be severely affected by the heat.â€

Prof Pfautsch said an appropriate selection of materials and colors combined with high-quality insulation were “the low-hanging fruit of climate-responsive urban design”.

“Government, industry and homeowners all play a role in making our neighborhoods cooler,” he said.

Under the 2022 National Building Code (NCC), all new Australian homes and apartments must meet a minimum energy efficiency rating of seven stars under the National Home Energy Rating Scheme (NatHERS).

But facing pressure from the construction lobby, South Australia and Tasmania recently declared a freeze on changes to the NCC for 10 years, instead of regular three-yearly updates.

Opposition Leader Peter Dutton followed suit in October, announcing the Coalition would also commit to a 10-year freeze on national building codes.

The Coalition said Labour’s changes to the NCC had “added red tape and increased the compliance burden for new housing projects, raising costs for buyers”.

It claimed that raising minimum energy efficiency standards from six to seven NatHERS stars would add $60,000 to the cost of a new home – a figure disputed by industry groups.

The Australian Glass and Window Association estimated the cost at $5000, while the Australian Building Codes Board said it was closer to $2200 in 2021 terms.

“Our concern is that they are providing regulations for new housing that will not stand or be resilient in the face of a changing climate, as well as dismantling and threatening the uniformity of a national building code,” Strachan. said.

She added that another problem was the NatHERS system using outdated climate data, leading to skewed assessment results.

“Until two years ago NatHERS was using old climate data up to 1990, which did not reflect the current situation and also the climate of the future project,” she said.

“Therefore climate zones like Victoria, the ACT and Tasmania in particular were going up in their energy rating report if they used a dark colored roof it could have been up to half a star … so that was the motivation.†€

Strachan said the result was “locking people into future housing stock based on data that is not really current”.

“These houses are going to be there for 50 years, they’re going to be there and they’re going to be lived in as we move into this changing climate,” she said.