The clean up bill from Tasmania's bushfires last month is yet to be determined.

Crews have begun clearing the ruins of more than 100 properties which have mostly laid untouched since the blaze.

Project manager Levi Causon from contractor Hazel Brothers says workers are assuming every house contains asbestos.

"The key issue there is to stop it going airborne, both when we handle it, transport it and dispose it," he said.

Mr Causon says it is unclear how much it will cost to clear each property.

Recovery coordinator Michael Stevens says the final cost is also uncertain.

"We haven't done our costings yet. Almost 300 properties have registered for assistance packages, but work can't begin without the approval of insurers," he said.

So far only 91 properties have received approval.