Tasmania Police said officers responded to blazes at Herdsmans Cove and Bridgewater about 1.50am on Sunday, February 11.

Police said a pile of mattresses were pushed under the cellar of a residence in Gangrell Place, before being set alight. 

The residence had been vacant for the past three weeks and about $5000 damage done to the property.

A fire at Cowle Road, Bridgewater was contained to a front room and caused about $8000 worth of damage. 

Members from the Glenorchy Criminal Investigation Branch are investigating both matters, in conjunction with the Tasmania Fire Service. 

Police said the incidents did not appear to be linked. 

Any members of the community with information about either fire has been asked to come forward.