Four fire engines and around 25 firefighters were called to a fire at a maisonette on The Coppice in West Drayton.
Part of a maisonette on the first and second floor of a three-storey block was damaged by the fire. One man left the building before the Brigade arrived. There were no reports of any injuries.
The Brigade was called at 1409 and the fire was under control by 1513. Fire crews from Hillingdon, Heathrow and Southall fire stations were at the scene.
The cause of the fire is under investigation.