One year on from the news of cracks emerging in the Opal Tower, it is time to reflect on what changes have occurred over these past 12 months.

Since the events of Opal Tower at Olympic Park last Christmas Eve, and the subsequent night-time evacuation of residents from Mascot Towers in June, high-rise apartment defects have become an issue in a way I have not seen in more than 40 years in the industry.

One year on ... cracks appeared in the Opal Tower on Christmas Eve last year. Credit:Dean Sewell

At Opal Tower, the last of the residents have only just been cleared to return to their homes. The builder has spent more than $20 million on repairs and relocation costs so far. The official reports point to engineering error as the main cause. At Mascot Towers, none of the residents of the 130 units are yet to return. Much work is to be done.

The real possibility of the building in which you own a unit – or the building you developed, designed or built – being on tonight’s telly has galvanised an unlikely alliance. For once the interests of unit owners, developers, builders, architects and politicians appear to be aligned. Nobody wants to be associated with the next Opal Tower or Mascot Towers.