At demolition sites in Japan, columns and walls are pulled down and demolished by heavy machinery or wire ropes. In a small-scale building in urban areas, columns and walls are pulled down by wire ropes. Before pulling down, workers damage the bottom part of the columns and walls for weakening them. However, if the damage of the columns and walls are too much, they fall down before use of wire ropes. As a result, they may crush workers. In this study, a fall prevention material was proposed with its installation method and verified its effectiveness by experiments. In an experiment of this study, steel pipes for supporting 3m-column were examined. The steel pipes were installed diagonally to the column. The column was loaded horizontally. We measured load and deformation until the steel pipe failed. As a result of experiments, it was found that the steel pipe buckled or the bolt supporting the steel pipe damaged. We concluded that this method is effective because the steel pipes were found to be sufficiently strong against the load generated in the steel pipes when the columns fell.