He said the adjoining annex will also be operational from tomorrow as power supply has been restored there.
"The PWD and other workers like carpenters and engineers are working day and night to refurbish Mantralaya," Bhujbal said, adding that the remaining four floors, gutted in the fire, will be ready for use in the next three months.
"After the structural audit team inspects the fire-affected areas, refurbishing of these floors will be undertaken," he said.
So far, 30 trucks have carried the debris from the top four gutted floors, he said after reviewing the renovation work at Mantralaya today.
Chief Minister Prithviraj Chavan will operate from Mantralaya's first floor office of Health Minister Suresh Shetty, while Deputy Chief Minister Ajit Pawar will function from Water Resources Minister Sunil Tatkare's office on the second floor.