Ten fire engines and around 70 firefighters were called to a flat fire on Lenham Road in Thornton Heath.
Part of the ground and first floors and the whole of the roof of a mid-terraced house converted into flats were alight, as well as part of the ground floor of a neighbouring property. There were no reports of any injuries.
Station Commander Alec McNally, who was at the scene, said: “Crews worked hard to bring the fire under control as quickly and safely as possible.
“The blaze was producing a significant amount of smoke and we encouraged nearby residents to keep their windows and doors closed while crews brought the incident under control.”
One of the Brigade's 32-metre turntable ladders was used at the scene as a water tower to tackle flames from height.
The Brigade's Control Officers took the first of eight calls to the fire at 0218 and sent crews from West Norwood, Norbury, Woodside, Beckenham, Forest Hill, Croydon, Tooting and surrounding fire stations to the scene. The fire was under control by 0429.
The cause of the fire is under investigation.