Six fire engines and around 40 firefighters were called to a fire at a house on Chelverton Road in Putney.
Most of the ground floor, first floor, second floor and roof of a three storey mid-terraced house was destroyed by fire.
One man left the property before the Brigade arrived. He was suffering from smoke inhalation and was taken to hospital by London Ambulance Service.
The Brigade's 999 Control room officers received the first of 14 calls at 1503 alerting them to the fire. They deployed crews from Chelsea, Richmond, Kensington, Tooting, Wandsworth and Soho fire stations. The fire was under control by 1844.
The cause of the fire is under investigation.