Six fire engines and around 40 firefighters tackled a fire at a semi-detached house with a loft conversion on Friars Avenue in Southgate.
The loft conversion was destroyed by the fire. Eight people left the building before the Brigade arrived. One man was treated on scene by London Ambulance Service.
One of the Brigade's 32-metre turntable ladders was used at the scene as an observation tower to help fight the fire from above.
Control Officers took the first of nine calls at 0028 and mobilised crews from Finchley, Tottenham, Barnet and surrounding fire stations to the scene. The fire was under control by 0144.
The cause of the fire is under investigation.