Four fire engines and 21 firefighters and officers were called to a fire at a house in Benledi Road, Poplar.
The second floor of the terraced house was destroyed by the fire and part of the roof was damaged. One man, one woman and a child left the property before the Brigade arrived. The man was taken to hospital by London Ambulance Service crews.
The Brigade's 999 Control Officers took 10 calls to the fire.
The Brigade was called at 0854 and the fire was under control at 1012. Fire crews from Poplar, Plaistow, Millwall and Stratford fire stations attended the scene.
The cause of the fire is under investigation.