Six fire engines and around 40 firefighters tackled a house fire on Copland Avenue in Wembley.
The roof and most of the first floor were destroyed by the fire. Two people left the building before the Brigade arrived and were taken to hospital.
One of the Brigade’s 32m turntable ladders was used at the scene as a water tower to help fight the fire from above.
Control Officers took the first of eight calls at 0550 and mobilised crews from Wembley, Northolt, Park Royal and surrounding fire stations to the scene. The fire was extinguished by 0803.
The cause of the fire is under investigation.