Abstract: A steel truss (10) spanning an opening (11) in a load-bearing CMU wall (111) is used as a structural support from which to hang hangers (12) having steel plates (13) on their lower ends. U-blocks (14) are placed on the hangers, and the space (20) between adjacent U-blocks (14) is filled with mortar. After the mortar hardens (typically 24 hours later), the trench formed by the hollow areas (15) in the U-blocks is filled with concrete, thus encasing the steel truss (the height of the truss is less than the distance from the lower interior of the U-blocks to the bottom of the CMUs above the U-blocks) and forming a steel-reinforced structural beam across the opening (11). CMUs (17) are then laid on top of the structural beam to continue the load-bearing wall above the opening.The truss preferably has attached at each end thereof a steel saddle (16) which serves to center the truss in the U-blocks.