A construction panel for use in the erection of buildings comprising a panel of castable construction material of predetermined thickness, and having first and second sides; a plurality of structural members, reinforcing the panel on one side, at least some of the structural members comprising a generally linear edge, and a generally zig-zag edge, and a web extending between the linear edge and the zig-zag edge, the zig-zag edges defining apexes, and root portions; the apexes, being embedded in one side of the panel thereby securing at least some of the structural members to the panel; recesses formed in the web extending substantially from the apexes to the root portions; and, generally triangular indentations formed in the web throat portions adjacent to but spaced from the recesses. Also disclosed is a method of constructing a level portion of a building.