Four fire engines and around 25 firefighters were called to a house fire on Shackleton Road in Southall.
The front door was damaged by fire and there was smoke damage throughout the end-of-terrace house.
Eight adults were rescued by fire crews wearing breathing apparatus.
The Brigade's 999 Control officers received the first of four calls at 0141 and deployed crews from Southall, Ealing and Hillingdon fire stations. The incident was under control by 0223.
The cause of the fire is under investigation by the Brigade's fire investigation team and the Met police.