New home design mistake costing Aussies $700 a year in wasted energy

Australian homeowners are wasting hundreds of dollars on energy bills because of one simple design flaw.

The cost-of-living crisis is biting into the budget of every household, with soaring energy prices making up a significant portion of rising costs.

New research from UNSW and Western Sydney suggests a darker-coloured roof could be driving up the power bills of Sydney homeowners by at least 38 per cent, with more energy required to cool down the heat absorbent homes.

Darker colours are known to trap and absorb heat, while lighter colours are able to reflect it.

Last year, the average household in NSW spent $1827 on electricity.

The researchers claim a lighter-coloured cool roof could reduce energy bills by up to almost $700 in slashed electricity usage.

White rooftops are a picturesque feature of cliffside towns in Greece and across the Mediterranean, but in Australia, the dominant trend in new housing estates are dark black rooftops.

Not only do they send energy bills soaring, but they increase the air temperature surrounding them, creating what is called the urban heat island effect.

Another urban design feature that contributes to this is blacktop roads, which can heat up to 75C during the harsh heat of the Australian summer.

The researchers have found reflective sealants painted over black roads can reduce the temperature by up to 13C.

White or lighter-coloured roofs can reduce heat inside a home and neighbourhoods, boost the efficiency of air conditioners and make solar panels work better.

In NSW, state government plans to ban dark roofs were scrapped in 2022 as part of an abandoned idea to upgrade the state’s planning policies.

While South Australia’s housing minister Nick Champion announced he will move to ban dark roofs in a new housing development in the north of Adelaide.

As the population of capital cities grow and the average temperature continues to climb year on year, cutting heat wherever possible is becoming an urgent priority.

Planting more trees in urban areas can also help provide shade and leafy areas are a proven method of reducing the urban heat island effect.