Hi,

My zinc roof at my balcony kinda leaks badly when it rains heavily. Beneath the zinc roof, there are plaster ceiling and they are already brownish in colour - not sure if it's due to the leakage or simply the paint is not good enough.

One part of the plaster ceiling eventually fell off and I could now take a peek at the leaks when it rains and seems like it's mainly leaking at the roof joints / "paku".

Do you know what to do to fix this permanently? Apply silicone on the paku area? Or something else?