The purpose of this study is to make a guide for the galvanic corrosion prevention in the building piping system. Water loopingtests were performed for 1 year. The galvanic corrosion behavior of the some piping materials were evaluated with a monitoring the corrosion potentials, the galvanic current and the corrosion appearances of the specimens. The main results are followings; 1) The galvanic current tends to decrease with time. An order of the level of the galvanic current is as following. (Higher) A1>Zn/Fe>Fe>brass>Cu and gunmetal (Lower). 2) In the case of the galvanic couple with Al as anode, Al severely corroded in hot water loop test. 3) An insulation between the anode and the cathode, and thier distance for the galvanic corrosion prevention were understood for the buiIding piping system.
