Police are investigating a deliberately lit house fire at Ravenswood on Saturday night.

Tasmania Fire Service and Tasmania Police attended the fire at 6 Hazelwood Parade, Ravenswood about 7.40pm.

The unoccupied house was extensively damaged, with an estimated damage bill of around $150,000. No one was injured in the fire.

Anyone who has information regarding this incident, or noticed suspicious activity in the area around the time of the fire, is asked contact Launceston Police on 6777 3945 or anonymously by calling Crime Stoppers on 1800 333 000 or online at crimestoppertas.com.au