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Figure 2-71.—Permanent lateral bracing in a truss.
Step 1.
Step 2.
Step 3.
Position the first roof truss. Fasten it to the
double top plate with toenails or metal
anchor brackets. A 2- by 2-inch backer
piece is sometimes used for additional
support.
Fasten two 2 by 4 braces to the roof truss.
Drive stakes at the lower ends of the two
braces. Plumb the truss and fasten the
lower ends of the braces to the stakes
driven into the ground.
Position the remaining roof trusses. As
each truss is set in place, fasten a lateral
brace to tie it to the preceding trusses. Use
1 by 4 or 2 by 4 material for lateral braces.
They should overlap a minimum of three
trusses. On larger roofs, diagonal bracing
should be placed at 20-foot intervals.
The temporary bracing is removed as the roof
B. Metal bracket.
sheathing is nailed. Properly nailed plywood sheathing
is sufficient to tie together the top chords of the trusses.
Permanent lateral bracing of 1- by 4-inch material is
recommended at the bottom chords (fig. 2-71). The
braces are tied to the end walls and spaced 10 feet OC.
Anchoring Trusses
When fastening trusses, you must consider
resistance to uplift stresses as well as thrust. Trusses are
fastened to the outside walls with nails or framing
anchors. The ring-shank nail provides a simple
connection that resists wind uplift forces. Toe nailing is
sometimes done, but this is not always the most
satisfactory method. The heel gusset and a plywood
gusset or metal gusset plate are located at the wall plate
and make toenailing difficult. However, two 10d nails
on each side of the truss (fig. 2-72, view A) can be used
Figure 2-72.—Fastening trusses to the plate: A. Toenailing;
in nailing the lower chord to the plate. Predrilling may
be necessary to prevent splitting. Because of the
single-member thickness of the truss and the presence
of gussets at the wall plates, it is usually a good idea to
use some type of metal connector to supplement the
toenailings.
The same types of metal anchors (fig. 2-72, view B)
used to tie regular rafters to the outside walls are equally
effective for fastening the ends of the truss. The brackets
are nailed to the wall plates at the side and top with 8d
nails and to the lower chords of the truss with 6d or
1 1/2-inch rooting nails.
INTERIOR PARTITION INSTALLATION
Where partitions run parallel to, but between, the
bottom truss chords, and the partitions are erected before
the ceiling finish is applied, install 2- by 4-inch blocking
2-44
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