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
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.
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
Metal is an alternative to wood framing. Many
buildings are framed entirely of metal, whereas some