Ten fire engines and around 70 firefighters tackled a fire at a house on Hadley Green Road in Barnet.
A detached house undergoing refurbishment was destroyed by fire. The structure subsequently suffered a partial collapse. There were no reports of any injuries.
One of the Brigade's 32-metre turntable ladders was used at the scene as a water tower to tackle the fire from above.
Control Officers took the first of eight calls to the fire at 0110 and mobilised crews from Southgate, Barnet, Finchley and surrounding fire stations to the scene. The fire was under control by 0448, but crews remained on scene throughout the day damping down hot spots.
Due to the unsafe structure of the building, the cause of the fire is currently recorded as undetermined.