Six fire engines and around 40 firefighters tackled a house fire on Greenwood Close in Morden.
The roof of a two-storey terraced house, with a loft under construction, was completely destroyed and part of the first floor was damaged by the blaze. There were no injuries reported.
The Brigade was called at 0258 and the fire was under control at 0442. Fire crews from Wimbledon, New Malden, Mitcham, Sutton, Tooting and Kingston fire stations attended the scene.
The cause of the fire is under investigation.