Four fire engines and around 25 firefighters tackled a flat fire on East Avenue in Hayes.
Part of the ground floor of a terraced house converted into flats was damaged by fire. One woman was assessed on scene.
The Brigade was called at 1431 and the fire was under control by 1515. Fire crews from Southall, Twickenham, Heston and Northolt fire stations attended the scene.
The cause of the fire is under investigation.