The Insurance Disaster and Response Organisation (IDRO) has released preliminary estimates of $20 million for the cost of insured damage from the Victorian bushfires.

An estimated 136,000 hectares of bushland and farming land has been lost as a result of more than 480 fires burning throughout Victoria.

About 10,000 firefighters converged on the blazes, many of them venturing from NSW and SA to lend a hand.

IDRO Victorian Co-ordinator Peter Jamvold says the fires across the state in the past few weeks have damaged homes, motor vehicles and farming property while livestock losses have been significant.