Four fire engines and around 25 firefighters were called to a fire at a vehicle repair workshop on Eastbournia Avenue in Edmonton.
A car within the single-storey unit was destroyed by the blaze and the roof of the garage was damaged. There were no reports of any injuries.
A London Fire Brigade spokesperson said: “The alarm was raised by a member of the public who smelt burning and saw smoke in the roof area of the building.
“They called the garage owner and then called the fire brigade.
“When crews initially arrived on scene, they had to cut away the metal roller shutter doors to gain access before firefighters wearing breathing apparatus could tackle the fire.”
The Brigade was called at 0029 and the fire was under control by 0133. Fire crews from Enfield, Chingford and Edmonton fire stations were at the scene.
The Brigade’s fire investigators believe the fire was accidental and caused by an electrical fault within the vehicle.