Eight fire engines and around 60 firefighters were called to a fire at a house in Chiltern Road in Sutton.
Part of the first and second floors and roof of the property were damaged by fire. The staircase from first to second floor level was also destroyed by fire.
The Brigade was called at 0906 and the fire was under control at 1049. Fire crews from Sutton, Wallington, Mitcham, Wimbledon and New Malden fire stations, along with colleagues from Surrey Fire and Rescue Service, attended the scene.
The cause of the fire is under investigation by the Metropolitan Police Service.