Four fire engines and around 25 firefighters were called to a fire at house on Wilsham Street in Shepherd's Bush.
Half of the ground floor and part of the first floor were destroyed by fire.
Five people left the property where the fire started, as well as three people from the next door building before the Brigade arrived. They were treated on scene for smoke inhalation.
Control Officers took their first call at 0107 and mobilised crews from North Kensington and Hammersmith fire stations attended the scene. The incident was over for firefighters at 0213.
The cause of the fire is under investigation by the Brigade's fire investigators and the Met Police.