Four fire engines and around 25 firefighters were called to a house fire on Binns Road in Chiswick.
Part of the ground floor of a semi-detached house was damaged by fire. There were no reports of any injuries.
Station Commander Brett Loft, who was at the scene, said: “A dog ran out of the house uninjured, and another dog was rescued by firefighters wearing breathing apparatus.
“The dogs were treated on scene and checked over by the RSPCA.
“There were a lot of possessions and clutter inside the house which made it challenging for firefighters.
"Hoarding means exit routes can become blocked, making self-evacuation more difficult. Fires can also spread much faster, especially when there are lots of flammable items such as newspapers or cardboard."
The fire is believed to have involved smoking.
The Brigade was called at 0713 and the fire was under control by 0824. Fire crews from Chiswick, Acton, Hammersmith and Richmond fire stations attended the scene.