A 36-storey tower at Sydney Olympic Park is evacuated putting thousands of residents on the street on Christmas Eve. Building movement, loud bangs and big cracks are reported. All this in a building that has opened only recently. The architect, structural engineer and builder are all respected players in the industry.

Much time will now be spent to find cause and culprit. Is the problem a significant structural issue, as it appeared from first reports? And if it is, is it the fault of an individual error by designer or builder or a sign of a wider problem in the industry?

At this stage we cannot say for sure, but we can say that away from the headlines a pattern is emerging industry-wide. Down the road from the Opal building, a relatively new, high-rise residential building has not made front page news but is also having problems. The structural failure has been more gradual. The building's cantilevered balconies started sagging gradually soon after occupation. Some balconies have sagged as much as 180mm on the outer edges over three years. As a result, cracks have opened up, water runs away from the outlets and pools on the balconies. Major structural repair works are being commissioned.

A similar unreported story is to be told at a nearby 300-unit block. Structural deficiencies have led to major deflection of cantilevered concrete slabs. This structural defect is just one item in $6 million worth of waterproofing and other faults found in this new building.