I assumed you would realise this is about Tasmania
You know what they say about “assume” (ha-ha!)
This sounds like a question that’s more about what the owners corporation is allowed to spend its money on than whether or not it’s liable (it sounds like the balconies are lot property). What does the Tasmanian Act say? For instance section 119 of the NSW Act says this:
119 Work to rectify certain defects
(1) An owners corporation for a strata scheme may carry out work that is necessary to rectify any of the following defects–
(a) any structural defect in any part of a building comprised in a lot in the scheme that affects or is likely to affect the support or shelter provided by that lot for another lot in the building or the common property,
(2) An owners corporation may carry out the work at its own expense if the cost of the work cannot be recovered from some other person.
You may find something similar in Tasmanian strata law.