Q: I noticed moisture on my ceiling, which increased to drops. The diagnosis was a leak in the plumbing of the apartment above mine. Who is responsible to fix the plumbing? What about the damage that already occurred?

A: It is certainly prohibited to pour water that falls directly onto another’s property in a damaging manner. One is also liable for such damage. If the water is minimal and gets completely absorbed in the ceiling at first, though, the person is not required to prevent it (C.M. 155:4).

However, in the case of a drainage hole that overflows and floods a neighboring basement, the Rosh required the person to move his drainage hole, because the damage is great and the damaged party has no easy way to protect himself (C.M. 155:20). On this basis, the owner of the upper apartment is required to fix his leaky plumbing.

Regarding damage that already occurred, if the upstairs owner fixed the leaky plumbing promptly once the problem was diagnosed, he is exempt. However, if he tarried with the repair and the damage spread, he is liable (see Emek Hamishpat, Hilchos Shecheinim #27-28; Pischei Choshen, Nezikin 13:5[12-14]).