Ten people were taken to hospital after a balcony collapsed. Credit:Ben Rushton The 12 people and the furniture, including table and chairs, slid off the balcony, which was left hanging from the side of the duplex. One edge of the balcony came to rest on a car parked below. "They got up to go inside and the part of the balcony that connects to the house basically disconnected from the house and then went fairly vertically. They all just slid off it, so to speak," Inspector Bell said. "The first floor had about a one-metre wide patio on it. Some of them fell onto that, which stopped the fall, and half of them fell just straight down into the garage section, another three metres further." He estimated five of the group fell the full six metres into the garage section.

Lucky escape ... a collapsed balcony at the rear of a duplex at Lane Cove. Credit:Ben Rushton "Considering the distance they fell and the potential for injury - falling onto a hard surface, and various bits of furniture fell with them, table and chairs and all the rest of it - it was quite amazing the injuries weren't worse," he said. Six ambulances and a rescue helicopter were called to the duplex on the Pacific Highway, and paramedics joined police and Fire and Rescue NSW officers in a delicate 70-minute operation to rescue the casualties and secure the scene. "Some of them had to be stabilised with neck braces because of the potential for spinal injury," Inspector Bell said. "The ones that were on the first floor level on the patio, it was quite a narrow stairway and they had to lift them over their heads. As far as things go, the rescue went surprisingly smoothly," he said.

It's an eight-year-old deck which had stood the test of time, until now. What caused this will have to be investigated. Ten people were taken to Royal North Shore Hospital, he said. Eight were taken by ambulance to hospital with a range of spinal, pelvic and limb injuries, while two others later took themselves to the hospital for treatment. Inspector Bell said nine had since been released, but a 31-year-old woman remained in the intensive care unit and was expected to undergo surgery on Thursday for extensive fractures. Neighbours reported hearing a large crash from 300 metres away when the balcony collapsed. Inspector Bell said the duplex was an older, brick building that appeared to have been renovated. The deck was added eight years ago, he said.

"It's an eight-year-old deck which had stood the test of time, until now. What caused this will have to be investigated," he said. Engineers are expected to begin examining the site on Thursday morning. Lane Cove mayor Scott Bennison said the current system of having private inspectors certify buildings was not working and needed to change. He said the Building Professionals Board and state government bodies had contacted the council on Thursday, and the certification of the balcony, which was built in 2006, would be investigated. ''From our perspective, this is one of the problems that we have with certifiers, that when something goes wrong, we're not a part of the process,'' Cr Bennison said.

''We didn't participate or have control in that process and we have no feedback as to what should be done to prevent it from happening again.'' He called for councils to be given the role of overseeing private certifiers, with the ability to issue fines ''to keep them honest, so to speak''. ''When things go wrong, they go wrong badly,'' he said. ''Fortunately there has been no loss of life in this instance.''