The Tasmania Fire Service were called to the upper Brougham Street residence about 6.20pm.

The fire was going well when it arrived.

Launceston fire station officer Heath Bracey said the fire started in the main bedroom, but the exact cause was still being determined.

``We will be investigating the fire tomorrow morning and that will begin at 8.30am,'' Mr Bracey said.

It took three fire crews more than an hour to control the blaze.

The property, which is a temporary accommodation house from the Migrant Resources Centre, will be under fire watch overnight.

The family only moved to Tasmania from Afghanistan five weeks ago.