The number of properties rendered uninsurable because of severe weather will almost double to 735,654 by 2100 from the current number of 383,330, according to a report produced for local government by analysis platform Climate Risk Engines.
Leading climate risk analyst Karl Mallon, chief executive of Climate Valuation, which provides extreme weather analysis of the construction and development arenas to banks and the property industry, said an increasing number of properties were in the insurance "red zone", ABC.net reported.
"Premiums are going to increase and they may become unaffordable," Dr Mallon said.
He said, "When you buy a house or issue a mortgage you are taking on a 30-year commitment.
"In principle, an insurance company only takes a one-year view of the future.
"But what we are seeing is over 30 years there will be substantial changes.
"Someone might be able to afford an insurance bill today, but it doesn't mean they can later on in their mortgage."
Insurance Council of Australia spokesman Campbell Fuller said no region in Australia was uninsurable — for now.
"However, it is possible some regions may become difficult to insure in the future," he said.