Four fire engines and around 25 firefighters were called to a fire at a house on Felbrigge Road, Ilford.
A flat on the first floor was destroyed by fire. One person left the property before the arrival of the Brigade.
The Brigade was called at 1453 and the fire was under control at 1552. Fire crews from Dagenham, Romford, and Barking fire stations attended the scene.
The cause of the fire is under investigation.