This is often treated as a “how long is a piece of string?” question, but The Economist has performed a great public service by allowing an easy comparison of the length of this piece of string across many countries and over time.
Check it out yourself. For Australian readers, house prices today are almost 2.5 times what they were in real terms in 1986; and our price bubble (in CPI-deflated terms) turns out to be smaller than some countries (notably Belgium’s) but larger than the USA’s and UK’s.