The man suffered severe head injuries after falling around three-and-a-half metres onto a concrete floor with a fellow worker at the Lyons Road property at around 1.40pm.

Police said the men were performing paid roof-restoration work on the property when they fell through the roof of a pergola at the rear of the house.

The 53-year-old sustained serious head injuries in the fall, was treated at the site by ambulance paramedics before being taken to Sussex Inlet Oval and airlifted to St George Hospital by the Ambulance Rescue Helicopter from Albion Park in a critical condition.

The second man, a 50-year-old from Sussex Inlet, suffered rib and back injuries but was not transported to hospital.

A crime scene was established and examined by forensic specialists.

Work Cover has been informed and inquiries are continuing to establish the exact circumstances surrounding the incident.