Four fire engines and around 25 firefighters tackled a fire at an end of terrace house on Edrick Walk in Mill Hill.
A motorbike and the front door of the house were destroyed by the fire. Part of the fascia and fencing was damaged by the fire. Three people left the building before the Brigade arrived. One person was treated on scene by London Ambulance Service.
The Brigade was called at 0424 and the incident was over for firefighters at 0541. Crews from Mill Hill, Stanmore and Hendon fire stations attended the scene.
The cause of the fire is under investigation by the Brigade and the Metropolitan Police Service.