Figure 1-69.Backing for interior wall plates.
each block are fastened to the joists with two 16d nails.
Two 16d nails are also driven through each block into
the top of the wall.
Walls running in the same direction as the ceiling
joists require backing. Figure 1-68 (insert) shows how
backing is nailed to the top plates to provide a nailing
surface for the edges of the finish ceiling material.
Lumber used for backing usually has 2-inch nominal
thickness, although l-inch boards are sometimes used.
Figure 1-68 shows backing placed on top of walls.
The 2 by 4 pieces nailed to the exterior wall projects
from one side of the wall. The interior wall requires a 2
by 6 or 2 by 8 piece extending from both sides of the
wall. Backing is fastened to the top plates with 16d nails
spaced 16 inches OC. Backing is also used where joists
run at right angles to the partition (fig. 1-69).
The scuttle is an opening framed in the ceiling to
provide an entrance into the attic area. The size of the
opening is decided by specification requirements and
should be indicated in the blueprints. It must be large
enough for a person to climb through easily.
The scuttle is framed in the same way as a floor
opening. If the opening is no more than 3 feet square, it
is not necessary to double the joists and headers. Scuttles
must be placed away from the lower areas of a sloping
roof. The opening may be covered by a piece of plywood
resting on stops. The scuttle opening can be cut out after
all the regular ceiling joists have been nailed in place.
RECOMMENDED READING LIST
Although the following references
were current when this TRAMAN was
published, their continued currency
cannot be assured. You therefore need
to ensure that you are studying the
Carpentry, Leonard Keel, American Technical
Publishers, Alsip, Ill., 1985.
Design of Wood Frame Structures for Permanence,
National Forest Products Association, Washington,
Exterior and Interior Trim, John E. Ball, Delmar
Publishers, Inc., Albany, N.Y, 1975.