Four fire engines and around 25 firefighters were called to a fire at a house on Repton Close in Carshalton.
Almost half of the first floor of the semi-detached property was damaged by the fire. Two people left the building before the Brigade arrived. There were no reports of any injuries.
The Brigade was called at 1629 and the fire was under control by 1728. Fire crews from Wallington, Sutton, Mitcham and Croydon fire stations attended the scene.
The cause of the fire is believed to be accidental.