A resident on Anglesea St, where the man fell from, said he heard noises after midnight but didn't think much of it.
Peter Bell was dozing when he heard running footsteps on the path outside his house and then a yell.
"I heard a cry like a 'yoh'. Like surprise."
Mr Bell said he believed the man must have come to the edge of the street, which overlooks Hillsborough Terrace, without realising it.
The cul-de-sac is boarded by a railing and thick shrub including trees, dropping off down a steep bank without warning.
Public access steps on the other side of the road are blocked off by fencing for construction work.