Four fire engines and around 25 firefighters attended a fire on Elmwood Avenue in Feltham.
The soffit of an end-of-terraced house, as well as a neighbouring house, was damaged by fire. A shed, the external fascia of a garden room and part of a car was also damaged. 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: "If you smoke it is vitally important you stub it right out, preferably in an ashtray.
"Always ensure your cigarette is completely out when you’ve finished smoking it. If you don’t, you risk causing a fire.
"Firefighters recommend that you have a look at our online Home Fire Safety Checker to make sure there are no hidden hazards in your home.
"The online tool will ask you a series of questions that will help us work out the level of risk in your home, or the home of someone you care for. It only takes a few minutes to get tailored advice to keep yourself and loved ones safe from fire.”
The Brigade received the first of 16 calls at 1736 and Control Officers mobilised crews from Feltham, Heston and Surrey Fire & Rescue Service to the scene. The fire was extinguished by 1856.