Two building companies were fined a total of £72,000 after a series of safety failings led to a work accident injuring three workers.
The incident took place when a floor collapsed during the construction of a six-bedroom property in Trafford on 11 November 2011.
One man, a 47-year-old from Wythenshawe, has been unable to return to work since.
He received severe injuries requiring a five-week hospital stay after being hit by a falling concrete beam that weighed around half a tonne.
As well as losing the use of his left hand and being left with very limited use of his left arm, he also suffered a punctured lung, broken collar bone, fractured ribs and damage to his back.
His two colleagues sustained minor injuries during the incident, which took place on South Downs Road in Bowdon.
Work safety failings
Belmont Homes (Cheshire) Ltd and Sale-based Waymac Ltd were both prosecuted by the Health and Safety Executive (HSE) after its investigation revealed sub-standard planning that put several lives at risk.
Bricklaying firm Waymac was one of several contractors brought in by property developer Belmont to contribute to the construction of the mansion valued at £2 million, Liverpool Crown Court was told.
The floor collapsed when concrete beams were installed, the beams landing on top of the three men as they fell with the floor.
Work to lower a steel frame had been badly planned, the HSE investigation revealed, with neither company having considered the potential risk of collapse while the structure was temporarily weakened.
Work accident firms plead guilty
Belmont Homes (Cheshire) Ltd, of Budworth Heath, pleaded guilty to a breach of the Health and Safety at Work etc Act 1974 by failing to ensure the safety of workers and was fined £33,000 plus ordered to pay costs of £15,000.
Waymac Ltd, of Eastway in Sale, was fined £9,000 and ordered to pay £15,000 in prosecution costs after it pleaded guilty to a breach of the Construction (Design and Management) Regulations 2007 by failing to ensure the structure did not collapse as a result of its work.
Source: Manchester Evening News