Six fire engines and around 40 firefighters were called to a fire at a block of flats on Elvet Avenue in Romford.
Half of a ground floor flat was damaged by the fire. There were no reports of any injuries.
The Brigade was called at 1130 and the fire was under control by 1212. Fire crews from Romford, Hornchurch, Wennington, Dagenham, Poplar and Harold Hill fire stations were at the scene.
The cause of the fire is under investigation.