Four fire engines and around 25 firefighters were called to a flat fire in Whitehall Close, Uxbridge.
Part of the loft void was damaged by fire. One man was treated at the scene for smoke inhalation by London Ambulance Service crews and taken to hospital as a precaution.
The Brigade was called at 1850 and the fire was under control at 2041. Fire crews from Hillingdon, Hayes, Ruislip, and Heathrow fire stations attended the scene.
The cause of the fire is under investigation by the Brigade and the Metropolitan Police Service.