A couple in their 70s learned their home was on fire thanks to working smoke detectors, an official with the Summerside Fire Department said.
The fire broke out at around 6:30 a.m. on Thursday morning at the Fitzroy Street home, Chief Jim Peters said.
"There were flames in the back part of the house," he said. "The fire started in back porch. We believe it started in the wiring."
The provincial fire marshal's office said the fire was caused by a malfunction in the electrical system after electrical wires came in contact with a hot water heating pipe.
Peters said the result was "heavy smoke throughout the rest of the house."
The people who lived in the three-storey house will likely not be able to return for several months because of the extent of the damage, he said.