"The apparent increase in the use of interest-only loans by both owner-occupiers and investors might also be consistent with increasingly speculative motives behind current housing demand," the RBA said.

“At this stage the main risk from this strong investor activity appears to be that the extra demand may exacerbate the housing price cycle and increase the potential for prices to fall later.” That could pose risks to the economy if people reacted to declines in their wealth and loan…