Metal Framing

Figure 1-50.-Plywood sheathing. walls range in size from 4 by 8 feet to 4 by 12 feet with thicknesses from 5/16 inch to 3/4 inch. The panels may be placed with the grain running vertically or horizontally (fig. 1-50). Specifications may require blocking along the long edges of horizontally placed panels. Typical nailing specifications require 6d nails with panels 1/2 inch or less in thickness and 8d nails for panels more than 1/2 inch thick. The nails should be spaced 6 inches apart along the edges of the panels and 12 inches apart at the intermediate studs. When nailing the panels, leave a 1/8-inch gap between the horizontal edges of the panels and a 1/16-inch gap between the vertical edges. These gaps allow for expansion caused by moisture and prevent panels from buckling. In larger wood-framed buildings, plywood is often nailed to some of the main interior partitions. The result is called a shear wall and adds considerable strength to the entire building. Plywood sheathing can be applied when the squared wall is still lying on the subfloor. However, problems can occur after the wall is raised if the floor is not perfectly straight and level. For this reason, Builders prefer to place the plywood after the building has been framed. Nonveneered Panels some entire Although plywood is the most commonly used material for wall sheathing, specs sometimes call for Figure 1-51.—Typical metal stud construction. nonveneered (reconstituted wood) panels. Panels made of waferboard, oriented strandboard, and composite- board have been approved by most local building codes for use as wall sheathing. Like plywood, these panels resist racking, so no comer bracing is necessary in normal construction. However, where maximum shear strength is required, conventional veneered plywood panels are still recommended. The application of nonveneered wall sheathing is similar to that for plywood. Nailing schedules usually call for 6d common nails spaced 6 inches OC above the panel edges, and 12 inches OC when nailed into the intermediate studs. Nonveneered panels are usually applied with the long edge of the panel in a vertical position. METAL FRAMING Metal is an alternative to wood framing. Many buildings are framed entirely of metal, whereas some 1-30