Nottingham Crown Court heard Ronald Leslie Cordon suffers from short term memory loss and a permanent loss of movement in his left thumb after he fell from an unprotected wall while doing bricklaying work on a house in Mansfield.
The 63-year-old from Derby was knocked unconscious when he struck his head on some steelwork in the fall.
Health and Safety Executive inspector for Nottinghamshire, Angus Robbins, said Mr Ludgate had failed to report the incident to the HSE.
Mr Robbins said: "A series of errors resulted in a tragic incident causing permanent damage to a man's health, but given the circumstances this could easily have resulted in a fatality.”
He said an inspection of another of Mr Ludgate’s construction sites had found two employees at risk of falling from the unprotected front edge of a loading bay.
Mr Ludgate pleaded guilty to breaching the Health and Safety at Work Act and was fined £1,500.