Shadow Housing Minister Mark McGowan said 45 offices have sat empty under Mr Barnett's watch, costing taxpayers over $707,000 while almost $40,000 has been spent on empty car bays for public servants.
"At a time when household fees and charges have been going through the roof and State debt is blowing-out, it is unacceptable for such a huge amount to be spent on rent for unoccupied buildings," Mr McGowan said.
The worst examples include:
Mr McGowan said the Barnett Government had badly mismanaged the government building and management programme.
"These empty offices and car bays demonstrate the Barnett Government's failure to prevent tax-payers money being wasted while at the same time slugging ordinary West Australians more for household bills," Mr McGowan said.
"How can the Government justify moving agencies to plush premises in the city while wasting tens of thousands of dollars on empty office space?"
Mr McGowan said the Opposition has already revealed how one government agency moving out of government-owned premises into the new leased premises at the Optima Centre in Osborne Park had cost millions.
"When you include these figures along with the exorbitant cost of the Premier's new palace the cavalier approach of this Government to the spending of public money becomes obvious," he said.