PURPOSE: To safely and simply attach an outside wall member in a short time.

CONSTITUTION: A wire feeding mechanism 5 is hanged down by the crane wire 3 of a crane 2 through a balancing mechanism 4, and both the ends of the hanging wire 6 of the wire feeding mechanism 5 are connected to an outside wall member 7. The crane wire 3 is made to ascend and descend to approximately position the outside wall member 7 at an attaching position, and the outside wall member 7 is then supported by an installing machine 8 provided on a building skeleton, and drawn near with its ascent, descent and rotation for its accurate positioning, and heldly fixed to the building skeleton 1. Thus the outside wall member 7 is attached to the building skeleton 1.