New apartments built to current Australian standards could become dangerously hot within decades, according to University of Sydney research that raises questions for brokers financing apartment purchases in fast-growing, heat-exposed suburbs.
The study, published in Energy and Buildings, modelled apartment buildings in Redfern and Penrith under future climate scenarios and found significant gaps in thermal protection under the current National Construction Code.
Western Sydney residents could face almost double the indoor overheating risk of those closer to the coast, with apartments potentially too hot for comfort for around four weeks a year in Redfern and more than seven weeks a year in Penrith by the 2050s.
"Australia is building homes for the future using standards designed for the climate of the past," said lead researcher Shamila Haddad from the School of Architecture, Design and Planning.
Top-floor and west-facing apartments were flagged as particularly vulnerable due to afternoon sun exposure and heat absorbed through roofs.
That's a significant concern given how much new housing is destined for the region. Western Sydney is projected to need 25,636 new homes a year through to 2041 to keep pace with population growth.
The research found straightforward changes — external window shading, safe night-time ventilation, lighter roofing, and better insulation — could cut overheating risk by up to 94% in combination.
Haddad warned reliance on air conditioning isn't a reliable fallback, noting that "in a future heatwave combined with a blackout, many apartments simply won't be able to keep residents safe," and that cooling poverty means not everyone can afford to run it in the first place.
For brokers, this adds a longer-term factor for clients eyeing new apartments in Sydney's growth corridors. With apartment approvals up 22.4% year-on-year, much of the next wave will be built before any code changes land. Clients buying off-the-plan or in heat-exposed suburbs may start asking about passive cooling and orientation — factors that could shape resale value and running costs too.
Get the hottest and freshest property and mortgage news delivered right into your inbox. Subscribe now to our FREE daily newsletter.
