Abstract: Disclosed is a reusable device for assisting a carpenter by securely holding up one end of a joist while the carpenter nails the other end in place. A pair of vertical supports has a pair of legs extending out and away from the respective lower ends of the supports. The outer ends of the legs are connected by a joist support stirrup. Generally horizontal arms extend from the upper ends of the vertical supports. The outer portions of the arms are bent into generally U-shaped configurations so that their free ends oppose their respective vertical supports. The distance between the free ends of the arms and their respective supports is such as to snugly hold a standard beam inserted therebetween, thus ensuring that the joist hanger and the supported joist therewith do not shift laterally. Further, the device can be used to hold a facing board against the end of a joist.