Four fire engines and around 25 firefighters tackled a fire at a shop with dwellings above on Lower Clapton Road in Hackney.
Part of the void from ground to fourth floor was damaged by the fire. One adult was taken to hospital by London Ambulance Service.
One of the Brigade's 32-metre turntable ladders was used at the scene to help fight the fire from above.
The Brigade was called at 1002 and the incident was over for firefighters at 1103. Crews from Homerton and Stoke Newington fire stations attended the scene.
The cause of the fire is under investigation.