Six fire engines and around 40 firefighters tackled a house fire on Vivian Avenue in Hendon.
The roof a derelict detached house was destroyed by fire. Parts of the ground floor and first floor were also damaged. There have been no reports of any injuries.
One of the Brigade's 32m turntable ladders was used at the scene as a water tower to help fight the fire from above.
The Brigade's Control Officers received around 30 calls about the fire.
The Brigade was called at 1934 and the fire was brought under control by 2047. Crews from Hendon, Finchley, West Hampstead and Mill Hill fire stations attended the scene.
The cause of the fire is under investigation.