Eight fire engines and around 60 firefighters attended a house fire on Crown Lane in Southgate.
Part of a loft room in a semi-detached house was damaged by the fire. One person left the property before the Brigade arrived. There were no reports of any injuries.
Aerial ladders were used so firefighters could remove tiles from the roof to enable them be to tackle the blaze from above.
A London Fire Brigade spokesperson said: "This incident is a timely reminder of the importance of having smoke alarms fitted throughout your home.
"The occupant was alerted to this fire by a smoke alarm sounding, so they left their bedroom and saw the smoke. They left the property and a neighbour called the Brigade.
"Smoke alarms give the earliest possible warning of fire. As a minimum you should have smoke alarms on every floor - in the hallways and the rooms you use the most, plus a heat alarm in the kitchen.
"They should be tested regularly."
The Brigade was called at 2147 and the fire was under control by 0007. Fire crews from Southgate, Barnet, Finchley, Tottenham, Hornsey and Hendon fire stations attended scene.
The fire has been recorded as accidental and is believed to have been caused by overheating lighting.