Four fire engines and around 25 firefighters were called to a shed alight on New King's Road in Fulham.
A shed in the rear garden of a detached house was destroyed by the blaze and part of the ground floor of the property was damaged. Five people left the building before the Brigade arrived. There were no reports of any injuries.
The Brigade's 999 Control Officers took 45 calls to the fire.
The Brigade was called at 1734 and the fire was under control by 1826. Fire crews from Fulham, Wandsworth, Hammersmith and Tooting fire stations were at the scene.
The Brigade's fire investigators believe the fire was caused by a fault in a fridge freezer.