Assuming you are in NSW, under section 62 of the Strata Schemes Management Act, the Owners Corporation must maintain and repair common property – no excuses and no exclusions.
I would be telling the strata manager to get this sorted NOW or your next step will be to go to the CTTT where you will be seeking an order to have the work done and possibly also asking for compensation for the loss of tenants.
I would also, quietly, be wondering about the competence of a strata manager who doesn’t understand this most fundamental of strata laws.
If you are not sure how to go about seeking an order, click HERE and scroll down to the section on CTTT Orders. There you will find a description of the processes involved and links to the forms required.