Should the vertical leg of a lintel angle supporting brick veneer be placed tight against the backup material, or should it be placed tight to the backside of the veneer?
Lintel angles are usually placed with the vertical edge against the back face of the brick veneer. This will reduce the torsional stresses and twisting of the angle because it reduces the distance between the shear center and the center of the veneer and because the back face of the wall can help minimize angle rotation. The Brick Institute of America in Technical Note 31B states that for veneers supporting only the triangular portion of the masonry directly above the opening, torsional stresses usually are negligible compared to flexural stressess and can be safely ignored. The twisting associated with torsional loading, however, can be significant. Angles should be stiff enough to limit the twisting of the angle to 1_16 inch at the outside leg. With larger spans, the horizontal leg must be greater than 31_2 inches to provide lintel angles that are stiff enough to carry the higher loads. In such cases, it may not be possible to position the angle against the back of the veneer. In these circumstances, I recommend checking the angles for torsion any time they have significant torsional loads.