It has prompted calls for a Medicare-like model of bushfire insurance.

The paper from the Practical Justice Initiative at UNSW suggests Australia can no longer sustain a purely market-based model for bushfire insurance, due to the growing threat of climate change.

It predicts more than 445,000 Australian homes will be uninsurable within 30 years, rising to 718,000 homes by 2100.

Researchers pointed to how home insurance premiums in Townsville have more than doubled in the past three years, due to increasing flood risks. By 2100, the risk of a one-in-100-year flood in Townsville will have increased by about 130 per cent.

Premiums in California rose between 300 and 500 per cent after the 2018 wildfires. Insurers also refused to renew policies for more than 340,000 homes.

If this happened in Australia, vulnerable groups would be left to shoulder the burden of climate change, including potential loss of home value, researchers said.

It would force people impacted through no fault of their own to bear the full cost of rebuilding or repairing. It also provide those on fixed-pension incomes with a particularly stark choice: pay high premiums or risk losing their major asset

It could even trigger a property market crash, if hikes in insurance premiums are combined with tighter bank lending.

"One likely example of this kind of increase of inequality is where a whole area, such as the bushfire-prone Blue Mountains, were suddenly to lose their insurance cover," the report said.

"The effect of this kind of 'postcode ban' would be to drastically cut the value of major assets of all those within the postcode. Such events would create pockets of high inequality."

Lead researcher Professor Jeremy Moss said the issue of climate change and bushfire insurance also raised broader issues about how society should share the burdens of responding to climate change.

"We need to make decisions about how much risk individuals should be asked to bear and whether society should allow widespread 'climate disadvantage'," Professor Moss said.

Researchers said as adequate housing a basic right and governments had failed to spend enough on disaster mitigation, moving to a "fairness as social justice" bushfire insurance scheme may be warranted.

"Australia's current medical care system is operated according to this model, with Medicare providing medical treatment to individuals at low or no cost, regardless of their risks and choices," the report says.

While the new approach may be costly in the short term, it would avoid the "social blight" of large numbers of people going without basic requirements, researchers argued.