Colin Howles, 53, was photographed by an inspector from the Health and Safety Executive as he and a colleague replaced the tiles on a mid-terrace house on Wyndale Road in Bardsley.
Trafford Magistrates’ Court in Sale heard no scaffolding had been put up at the back of the property to stop either of the men falling nearly six metres to the ground below.
The HSE inspector issued a Prohibition Notice, ordering the men to come down from the roof immediately, when he visited the site as part of routine inspections in the area on 3 November 2010.
The court was told two scaffolding towers had been erected at the front of the house but no scaffolding had been put up when the men started work on the section of roof at the back of the property.
Colin Howles pleaded guilty to a breach of the Work at Height Regulations 2005 after he failed to take action to prevent workers being injured in a fall.
Howles, of Bardsley Vale Avenue in Oldham, was fined £350 and ordered to pay £600 in prosecution costs.
Speaking after the hearing, HSE Inspector Tom Merry said: “Mr Howles has more than 30 years’ experience in the building trade so should have known how to carry out the work safely. In fact, he erected scaffolding at the front of the house but not at the back.
“Not only did he risk his own life, he also risked the life of another worker by allowing extensive roof work to take place without scaffolding on both sides of the building.
“It is through sheer luck that neither he nor the other worker became one of the thousands of people who are killed or seriously injured in a workplace falls every year.”