不知道我有没有抓住重点Inter-floor leaks If there is an inter-floor leak, you and your neighbour are required to jointly carry out an investigation to establish the cause of the leak and proceed with the repair works. You should also both resolve the cost of repair. In cases like this, it is presumed that the leak has originated from the upper floor unit unless the owner can prove otherwise. Therefore, the owner of the upper floor unit cannot claim that the leak has not originated from a defect in his unit. He has to jointly investigate the cause with his lower-floor neighbour and proceed with any repairs required.