Tasmania Police is investigating a suspicious house fire at Rokeby overnight.

Tasmania Fire Service crews were called to the fire at Annabelle Street, Rokeby shortly after midnight and found the house well-alight upon arrival.

The house was unoccupied at the time due to a previous electrical fire at the residence.

Initial investigations indicate that the fire was deliberately lit. It is being treated as suspicious and police are investigating.

It will be determined in the coming days whether the property will be demolished. The damage is currently estimated to be between $80,000 and $100,000.

Anyone with information is asked to contact Bellerive CIB on 131 444, or Crime Stoppers anonymously on 1800 333 000 or crimestopperstas.com.au