To prevent water from being stolen in a multiple dwelling house by incorporating a three-way ball valve in a portion where a water supply pipe branches to each dwelling house of the multiple dwelling house, and suspending the supply of water in every dwelling house.

Three-way ball valves 17, 17a are incorporated in the portions where water supply horizontal pipes 9 branche off from a water supply vertical pipe 8, which are the portions where water supply pipes branche at every dwelling house 4 of a multiple dwelling house 3. For example, in the case of a multiple dwelling house in which one dwelling house is placed in each floor of a three-story building, the three-way ball valve 17 incorporated in a portion where the water supply horizontal pipe 9 of the first and the second floors branches is opened in three ways, and the valve 17a incorporated in the water supply horizontal pipe 9 of the dwelling house 4 at the third floor is opened in two ways to supply water. In suspending the supply of water to the dwelling house 4 which is a vacant room, the forms of the valves 17, 17a incorporated in portions where the water supply horizontal pipe 9 to the vacant room branches off from the water supply vertical pipe 8 are switched to open in two-way or in one-way, thereby closing ports of the valves 17, 17a communicated with the vacant room. Thus, the supply water can be suspended at every dwelling house 4 so as to surely prevent water from being stolen.