Four fire engines and around 25 firefighters were called to a house fire on Windmill Lane in Greenford.
Firefighters tackled a fire in the garden of a terraced house involving a gazebo and garden furniture. The blaze also spread to the external fittings of two neighbouring properties. There were no reports of any injuries.
The fire is believed to have been accidental and caused by the unsafe disposal of smoking materials.
A London Fire Brigade spokesperson said: “Fires caused by smoking materials including cigarettes, roll-ups, cigars and pipes, result in more deaths than any other type of fire. Stub cigarettes out properly and always dispose of them carefully.
"Make sure smoking materials are cold before emptying ashtrays. Preferably wet stubs before throwing them into a bin.”
The Brigade was called at 1702 and the fire was under control by 1918. Fire crews from Ealing and Northolt fire stations attended the scene.