Six fire engines and around 40 firefighters tackled a fire on Ensign Drive in Winchmore Hill.
Most of the first floor and roof of a detached house was destroyed by fire, along with a garage. Part of the first floor and roof of a neighbouring house was also damaged. One person was assessed at the scene by London Ambulance Service. A further person was taken to hospital as a precaution.
Control Officers took the first of 15 calls at 1349 and mobilised firefighters from Tottenham, Hornsey, Chingford, Finchley and Barnet fire stations to the scene. A 32-metre turntable ladder from Soho Fire Station also attended and was used as a water tower to help extinguish the fire from above. The fire was under control by 1538.
The cause of the fire is under investigation.