Four fire engines and around 25 firefighters were called to a bike workshop fire in a lean-to shed in a garden on Edmund Road in Mitcham this morning.
The lean-to shed was completely destroyed by the fire. The fire also destroyed a ground floor flat, half of a first floor flat and a small part of the roof.
The Brigade's 999 Control officers were first called at 0836 and the fire was under control by 1003.
Fire crews from Mitcham, Wimbledon and Tooting fire stations were in attendance.
The cause of the fire is under investigation.