Eight fire engines and around 60 firefighters were called to a fire at a mid-terraced house on Bournebrook Grove in Romford.
Most of the roof of one house was destroyed by fire. One resident left the property before the Brigade arrived.
Half of the roof and cladding on a neighbouring property were damaged.
Thankfully no injuries are reported.
Fire crews will remain on scene damping down hot spots for most of the afternoon.
The Brigade was called at 0953 and the fire was under control by 1256. Fire crews from Dagenham, Romford, Leyton, Harold Hill, Ilford, Barking and Poplar fire stations were at the scene.
The cause of the fire is accidental and due to hot works.