PITTSFIELD — Three residents of a Canal Avenue duplex were displaced after a small fire on Saturday led building inspectors to condemn the unit.

Officials have confirmed the cause of the fire at 18 Canal Ave. to be an act of arson carried out by a juvenile. They declined to specify how it was started.

Called in as a structure fire at about 1:04 p.m., the blaze was put out by the Pittsfield Fire Department in about 20 minutes, according to Deputy Chief Daniel Garner. Firefighters were able to contain the fire to the upstairs bedroom.

The fire damage alone was not enough to condemn the whole building, but the unit in which the fire began was condemned.

"Basically there were some hoarding issues," Garner said. "The building inspector and the health inspector shut it down."

Garner said the fire remains under investigation.

As crews finished up at the scene at Canal Avenue, they whisked away to an oven fire on Dalton Avenue.

"We were running around [on Saturday afternoon]," Garner said.

Contact Adam Shanks at 413-496-6376.