Six fire engines and 35 firefighters and officers were called to a fire at a house under refurbishment in Brunswick Mews, Marylebone.
Part of the ground floor, half of the first floor and most of the second floor of the three storey terraced house were damaged in the blaze. There were no reports of any injuries.
The Brigade was called at 1615 and the fire was under control at 1919. Fire crews from Paddington, Soho, Chelsea and Lambeth fire stations attended the scene.
The cause of the fire is under investigation.