Abstract: A prefabricated concrete building module comprises two pre-cast concrete end panels interconnected and interlinked to a pre-cast bridging panel providing a utility channel at at least one corner thereof, the channel aligning with a reinforcement formation on each side edge of each end panel.

Abstract: A brace for temporarily retaining a first panel and a second panel in abutting contact with a respective support member for each panel has two brace members, breakable end portions, removable brackets connectable to the end portions thereof, and a retaining members engageable in retaining apertures proximal disposed between the end portions and proximal thereto. The brace members are extended between the opposing panels, with the support members being placed in the brackets. The retaining member is inserted into each retaining member until each panel is held with the inner face abutting the retaining member and the outer face abutting the support member in the bracket. After application of the cementitious material, the breakable portions, brackets, and support member may be removed by breaking off the breakable end portions by application of a force thereto.