Eight fire engines and 60 firefighters were attempting to extinguish a blaze in a house on Churchill Road, Willesden, north-west London, in the early hours of Friday.
London Fire Brigade said in a statement it was called to the two-storey terrace at 1.35am, with crews attending from Willesden, North Kensington, West Hampstead, Park Royal and surrounding stations.
Station commander Neil Dickinson, who was at the scene, said: “The fire appears to have started on the first floor of the building and spread into the roof space of the house, where there is heavy smoke logging.
“Crews used cutting equipment to remove tiles from the roof and gain access to ensure the fire was under control.”
Soon after 4.30am the brigade declared the blaze was under control, with Mr Dickinson saying crews would stay on the scene for a number of hours damping down remaining hot spots.
London Fire Brigade said the cause of the blaze was being investigated.