HappyNow, owners corporations have the ability to prioritise repairs to common property. Even though the Act does not stipulate this, it comes down to common sense. If a building has many large costly repairs, if they were all to be actioned at once, the increase in levies for owners would be astronomical.
I have seen orders made by the NCAT in similar situations where the OC made decisions to repair one part of a building over another, and not action all common property repairs at the one time. The NCAT upheld the OC’s decision to do this due to the reasons I mentioned above. As proudsceptic mentioned, we don’t all the details of your matter, you could try mediate with the OC as a first step.