Firefighters received a call just after 1:30 a.m. Friday about a fire in a two-storey building on 1st Avenue between Bannantyne Avenue and Verdun Street.
The fire started on the first floor and spread quickly to the second floor and to the roof.
It took about 60 firefighters two hours to get the fire under control.
None of the residents were injured, but one firefighter was taken to hospital for an injury to his wrist.
The Red Cross is providing shelter for the residents.
The building is a total loss.