The building structure of the present invention comprises a rectangular box having ceiling and floor walls and four upstanding walls. The lateral edges of each of the aforementioned walls have L-shaped indentations therein which provide glue surfaces. These L-shaped indentations are mated together at the corner junctions of all walls in the box and are glued together and nailed so as to provide an integral rectangular box. Each wall comprises a plurality of panels joined together in side to side relationship. Each panel comprises spaced apart rigid sheet members, and the panels are joined together in side to side relation by means of elongated stretchers which extend between the spaced apart sheet members and interconnect the panels which are arranged in side to side relationship.