Is it responsible for the leakage upstairs and downstairs?

The division of responsibility for the leakage of the upstairs wall leading to the leakage of the downstairs wall. It depends on whether the upstairs water pipe leaks or the downstairs wall leaks due to the sewer leakage. If the upstairs owner's water pipe leaks, the losses caused to the downstairs neighbors should be borne by the upstairs owner. This responsibility must belong to the upstairs owner.

If the floor drain upstairs blocks the drainage, it will cause the loss of the wall downstairs. The owners upstairs should also be responsible.

If it is the downstairs loss caused by the rupture and seepage of public sewer pipes. Maintenance responsibility should be borne by the residential property.