Six fire engines and around 40 firefighters dealt with a house fire on Harefield Road in Brockley.
The fire badly damaged a flat roof and firefighters worked hard to limit the damage to the roof and the adjacent property's roof.
London Fire Brigade spokesperson said:
"The fire was discovered by a building working on a neighbouring property who raised the alarm by shouting and banging on the doors.
"A man and a woman left the property before the Brigade arrived. Thankfully there were no injuries.
"Firefighters carried out salvage operations to try and prevent water damage to belongings."
"The fire is believed to be caused by hot building work that had happened earlier in the day."
The Brigade was called at 1419 and the fire was under control by 1513. Fire crews from Lewisham, New Cross, Greenwich, Deptford and Forest Hill fire stations were at the scene.