A wall of scaffolding that collapsed at a central city building site today could have caused serious harm, says the boss of the building company.

Rick Herd, chief executive of Naylor Love, said no one was injured when the scaffolding, about three storeys high, collapsed this morning in high winds, leaving it hanging perilously over St Patrick's Square.

The scaffolding was on the site of the nearly completed Park Residences, a 28-storey apartment tower on the corner of Albert and Swanson Sts.

"At this stage we don't know [what happened]. This is a very serious situation and could have had some serious harm involved.


"We need to get to the bottom on why it collapsed. It was possibly a failure of some fixings back to the building," said Herd.

He said trees and poles in St Patricks Square prevented the scaffolding falling all the way to the ground.

A WorkSafe spokesman said it had been notified of the incident and was making initial inquiries.