Strata law is different from state to state but in Victoria, as in NSW and most other places, the Owners Corporation has a legally enforceable duty to maintain and repair common property (which the ceiling/floor between your flat and the one above almost certainly is). See section 46, below.
Basically, the OC or manager should be investigating whether the problem is in common property or caused by a fault in the lot above.
Once they have established that, they should either repair the common property pipes or insist that the owner upstairs fixes the problem in their lot. The key issue here is that it’s not up to you to pursue the lot owner – this is an Owners Corporation issue and your manager should be dealing with it directly.
The process for pursuing complaints in Victoria is very different from NSW. And with my lack of detailed knowledge in mind, you should definitely talk to someone in Victoria who has experience of this kind of thing, or at the very least call Consumer Affairs Victoria on 1300 55 81 81.
That said, as far as I can see, you need to fill in an official complaints form and attempt mediation before you can go to VCAT (the Tribunal) and seek orders. You’ll find a link to the official complaints process and forms HERE.
Now, having said that, I would be calling the manager and saying, “look, this is your responsibility and I don’t want to cause you any trouble but if I haven’t seen any progress on this within seven days, I’m afraid I have to start the official process and that involves making a complaint to the committee about you.”
If you don’t get the required response, then start the process by filling in the official complaints form with a complaint about the manager, not the other lot owner, for failure to maintain common property as required by section 46 of the Act.
I’m now hoping one of our Victorian Flatchatters will hop in here, put me right if I have said anything wrong and provide more reliable advice.
VICTORIAN OWNERS CORPORATIONS ACT 2006 – SECT 46
Owners corporation to repair and maintain common property
An owners corporation must repair and maintain—
(a) the common property; and
(b) the chattels, fixtures, fittings and services related to the common property or its enjoyment.