Paul Dwayne Retschlag, 42, pleaded guilty in the Launceston Supreme Court yesterday to one count of arson.

Justice Robert Pearce convicted Retschlag and jailed him for eight months, wholly suspended for two years.

The arson occurred about 8pm on November 21, 2012, when Retschlag set fire to a phone book he placed inside the meter box of the Housing Tasmania unit he rented in Gilham Avenue.

The meter box was recessed into a masonry wall outside the front door of the unit and was lined with timber framing.

The fire destroyed the power box and the electrical equipment inside it, and the ceiling nearby was smoke-damaged.

Retschlag later told police he had shared three-quarters of a bottle of bourbon with a neighbour before he lit the fire.

Justice Pearce noted that Retschlag had suffered from depression, was not taking his medication regularly, had just stopped long-term use of cannabis, and had to endure demanding and difficult neighbours.

"The defendant quickly admitted what he had done to the police and told them that he was desperate to get out of the unit complex," he said.

"That seems to be the motivation for his bizarre behaviour.

"He is to be sentenced on the basis that he intended only to damage the meter box and did not expect the fire to spread."

Justice Pearce said the fire might have spread further than it did, putting life and property at risk.

He said fire damage to Housing Tasmania properties was a considerable problem.