Four fire engines and 21 firefighters and officers were called to a fire at a block of flats in Tufnell Park Road, Islington.
The rear balcony of a first floor flat was destroyed by fire. Half of the rear balconies on the second, third and fourth floors was also damaged in the blaze. Thirty people left the building before the Brigade arrived.
The Brigade was called at 1415 and the fire was under control at 1545. Fire crews from Holloway, Islington, Soho and Paddington fire stations attended the scene.
The cause of the fire is under investigation.