Thieves made off with around £2,000 worth of scaffolding in Dulwich last week, smashing stairs in front of a house and causing thousands of pounds of damage in the process.
The incident in Underhill Road was carried out in broad daylight at 2pm, on the day that neither the owner, painters nor builders were in.
The owners of the scaffolding are now warning other builders that it could happen when you least expect it.
Gareth Berry, one of the scaffolders, said: “They took wooden boards and foam pieces that stop people bumping into the poles. They took 30 boards thirteen feet long, and twenty boards ten feet long.
“They smashed all the stairs in front of the house. It was the one day that the painters were not on site and the owner wasn’t in, and it was in broad daylight at 2pm!
“They were in such a rush. It’s stealing and it has a knock-on effect throughout the company and on our lives.
“Once you put your banner up it’s meant to be an unwritten rule that you don’t steal from your own.
“We do everything to try to prevent it like having an alarm and having the boards marked with our brand.
“They were throwing them off the building, hitting the floor and the steps causing thousands of pounds worth of damage, all in less than fifteen minutes.”
“I’d say to people, if you have someone you don’t recognise on your site, ask questions.”