Office vacancy rates in Melbourne could reach double figures in six months, according to a market report.
Colliers International says vacancy grew from 5.5% in September to 8.1% by the end of last month.
And there is 'more pain to come', according to Colliers' director Rob Joyes.
'Unfortunately it's looking like it will head to probably 10% (vacancy),' he said.
A rash of speculatively built stock before the market crash in the early 1990s pushed Melbourne's vacancy rate as high as 25%. 'Spec building' has since gone out of vogue, but there will still be an issue this year with excess supply.