Ten fire engines and around 70 firefighters tackled a fire at a house on Woodbourne Avenue in Streatham.
Most of the roof and third floor were damaged by the fire. A small part of the first floor was damaged by the fire. A ground floor flat was destroyed. Seven people left the building before the Brigade arrived. There have been no reports of any injuries.
Two of the Brigade's 32-metre turntable ladders were used at the scene as water towers to help fight the fire from above.
Control Officers took the first of seven calls at 1639 and mobilised crews from Tooting, Norbury, West Norwood and surrounding fire stations to the scene. The fire was under control by 1931.
The cause of the fire is under investigation.