Four fire engines and 21 firefighters and officers were called to a fire at a house converted into flats in Braemar Avenue in Neasden.
Part of the first floor and all of the roof of the property was damaged by fire. Approximately six people left the building before the arrival of the Brigade. Five further workers also evacuated before firefighters arrived.
The Brigade was called at 1718 and the fire was under control at 1834. Fire crews from Willesden, Wembley and Stanmore fire stations attended the scene.
The cause of the fire is believed to be accidental.