DC Kennedy Homes was fined £7,500 and ordered to pay another £7,500 in costs after being prosecuted by the Health & Safety Executive.
Manchester Crown Court heard that Ian Smith, 64, was killed when he fell from an unstable ladder. Smith was working on a project to build six new semi-detached houses in Dale Gardens, on Easedale Road in Bolton, on 19 December 2007 when he fell five metres to the ground.
HSE's investigation found that DC Kennedy Homes had allowed work to be carried out on the first and second floors of the house, before the stairs had been fitted. The ladder, which was used to reach the second floor, had not been secured and was missing its rubber feet.
DC Kennedy Homes, of Ladybridge Lane in Bolton, pleaded guilty to breaching Section 2(1) of the Health and Safety at Work etc Act 1974 by failing to ensure Mr Smith's safety. The company was ordered to pay an additional £7,500 towards the cost of the prosecution as well as the fine.
Polly Tomlinson, HSE principal inspector for Greater Manchester, said: "This was a tragic incident that could easily have been prevented if DC Kennedy Homes had put more thought into the safety of its employees. The ladder Ian Smith used was dangerous as the rubber feet were missing and it wasn't tied to the wall to stop it slipping.
"But more importantly, Mr Smith should never have been expected to use a ladder in the first place. If the work had been planned properly, the stairs would have been fitted before work was carried out on the first and second floors of the house.
"Instead Mr Smith had to use a ladder to access the second floor, putting his life at risk. Other employees were also put in danger by the unprotected open edges.
"I hope this case will act as a warning to other house building companies to improve their safety standards, to prevent more people dying at work in the future."
The prosecution is being highlighted ahead of the launch of HSE's national Shattered Lives campaign today, 1 February, which is urging companies to take simple steps to prevent serious injuries from slips, trips and falls.
Falls from height are the biggest single cause of workplace deaths in the UK, and more information on preventing injuries.