Karl Davis fell through a first floor open window frame when a guard-rail gave way at Everton’s Finch Farm centre in Halewood, Merseyside.
Davis lay in a coma for three months before he died in May 2007, less than a week after his 43rd birthday.
Kier pleaded guilty to charges relating to failing to ensure the safety of workers and was ordered to pay £43,993 costs in addition to the fine.
Liverpool Crown Court heard how a rubbish chute had been attached to a temporary guard-rail at the window frame, leading to a skip below.
The Kier site management team had failed to ensure that the guard-rail could withstand the weight of the chute and materials being thrown down it.
Robert Hodkinson, an HSE inspector, said: “What is incredibly sad about this incident is that a man lost his life when equipment installed to make the work safer failed.
“If Kier North West had ensured the rubbish chute was attached to a structure which could support its weight then Mr Davis would still be alive today.”