Five people living in a registered two-unit house in downtown Barrie are being provided emergency accommodations by the Red Cross after a "stubborn" fire spread to the attic area, Sunday night.
Barrie firefighters responded to the Mary Street scene, between Ross and Dunlop streets, shortly after 7:30 p.m, Sunday.
Carrie Clark, the city's assistant deputy fire chief, said no civilians or firefighters were injured.
One dog had to be rescued, however.
The fire had spread under the soffits and siding before getting up into the roof area.
There was heavy smoke and water damage to the house.
Damages have been estimated at $100,000.
The official cause will go down as undetermined, Clark told BarrieToday, because there were several potential ignition sources.
Investigators wrapped up their on scene early this morning.
The tenants did not have rental insurance, Clark added.