Australian homes are among the most expensive in the world when household incomes and rents are taken into account, International Monetary Fund figures show.
As part of a move to push governments to act against housing bubbles, the fund unveiled comparative data on Thursday morning intended to underline the high cost of homes.
It shows rising prices have pushed two key measures of home values - the ratios of house prices to incomes and prices to rents - well above their long-term averages.
With houses selling for more than four times the average household income, the IMF said this ratio in Australia was much higher than its historical average.
A 24-country comparison showed that Australian homes were second only to those of Belgium when judged by this measure.
The other metric it used to measure home values was the ratio of prices to rents. This was also much higher than the long-term average in Australia, which by this criterion ranked fifth most-expensive behind Belgium, Norway, New Zealand and Canada.
IMF deputy managing director Min Zhu said the fund was publishing the data in an attempt to ensure governments moved from a policy of ''benign neglect'' regarding house prices. ''Our research indicates that boom-bust patterns in house prices preceded more than two-thirds of the recent 50 systemic banking crises,'' Mr Zhu said in a blog post.
He also noted Australia was among a handful of countries where price-to-income and price-to-rent ratios were ''well above'' their historical averages.
The IMF data is the latest indication of the high cost of Australian housing, which some economists believe has started to deter buyers. In April, Barclays economist Kieran Davies said prices were ''flashing red'' with prices at 4.3 times household income and 28 times annual rent, both just below record highs.
In a sign the market might be cooling, however, capital city prices recorded their first monthly fall in a year during May, according to RP Data-Rismark. Sydney's median house price fell 1.1 per cent in the month to $678,500 and Melbourne's dipped 3.6 per cent to $555,000.
Australian houses have long stood out as expensive when compared with other nations. But Mr Zhu conceded that detecting overvaluation was ''more art than science'' and it was important to also consider factors such as credit growth and household debt.
On this front, recent figures have been less dramatic. Latest Reserve Bank of Australia figures show housing lending growing at its fastest annual pace in three years, but it is still well below the pace reached before the global financial crisis.
Household debt as a share of disposable income is also at a three-year high, at 148.8 per cent, but remains below record highs.
In order to prevent housing markets from overheating, the IMF recommends governments consider rules to rein in riskier bank lending, which Australia has so far avoided.
Mr Zhu said more than 20 countries had adopted ''macroprudential'' policies such as caps on low-deposit loans or debt-to-income ratios in recent years.
- Sydney Morning Herald