Nantucket firefighters responded Wednesday morning to a report of a fire at 14 Miacomet Avenue.
The Inquirer and Mirror says the fire was mostly contained to a single bedroom in the home and its contents were significantly damaged.
Fire crews had to cut a hole in the roof of the duplex to vent heat while fighting the fire.
Fire officials believe the blaze was caused by excessive use of extension cords.
There were no injuries reported in the incident.