Firefighters were called to the scene on Joicey Boulevard near Avenue Road just before 3 a.m. Crews arrived to find the three-storey home fully engulfed in flames.
It took firefighters about an hour to bring the fire under control. No one was hurt.
The fire marshal has been called in to investigate.
CBC Toronto overnight reporter Tony Smyth posted this video from the scene:
The fire has led to the closure of Joicey Boulevard. Our traffic reporter Laurie Turcotte has the details: