Six fire engines and around 40 firefighters tackled a fire in a car workshop on Delamere Road in Hayes.
The single storey workshop was partly damaged by the blaze. The fire caused a huge amount of black smoke into the local area.
The workshop was at the rear of a shop and flats of two stories. Around 30 people left the flats and surrounding properties before the Brigade arrived.
The Brigade was called at 0626 and the fire was under control by 0848. Southall, Hillingdon, Hayes, Ealing, Northolt and Heathrow fire stations were at the scene.
The cause of the fire is believed to be an electrical fault in a car stored in the workshop.