Four fire engines and around 25 firefighters tackled a fire at a residential block on North Circular Road in East Finchley.
Part of a flat on the third floor was damaged by the fire. One man was treated on scene and taken to hospital by London Ambulance Service crews.
The Brigade's 999 Control Officers took 24 calls regarding the blaze. The first call was taken at 0711 and the incident was over for firefighters at 0820. Crews from Hendon, Finchley and Mill Hill fire stations attended the scene.
The cause of the fire is under investigation.