A tap test is used to inspect the full surface of exterior walls, and its results can vary depending on the investigator’s senses. In this study, it was examined how to improve the testing accuracy for detecting lifting of RC wall tiles. Research has shown that diagnosis techniques must be considered from the perspective that judgment results vary, that diagnostic accuracy can be improved by accumulating techniques, and that work time varies greatly among individuals. As a result, it is beneficial for the investigator to confirm the diagnosis criteria with several people during the preliminary on-site meeting.
