Figure 5-3.Drywall fasteners.
sanding, ensure youre wearing the required personnel
protective gear to prevent dust inhalation.
A foot lift helps you raise and lower drywall sheets
while you plumb the edges. Be careful when using the
foot liftapplying too much pressure to the lift can
easily damage the drywall.
Fasteners
Which fasteners you use depends in part upon the
material underneath. The framing is usually wood or
metal studs, although gypsum is occasionally used as a
base. Adhesives are normally used in tandem with
screws or nails. This allows the installer to use fewer
screws or nails, leaving fewer holes that require filling.
For reasons noted shortly, youll find the drywall screw
the most versatile fastener for attaching drywall to
framing members.
NAILS. Drywall nails (fig. 5-3, view A) are
specially designed, with oversized heads, for greater
holding power. Casing or common nailheads are too
small. Further, untreated nails can rust and stain a finish.
The drywall nail most frequently used is the annular ring
nail. This nail fastens securely into wood studs and
joists. When purchasing such nails, consider the
thickness of the layer or layers of drywall, and allow
additional length for the nail to penetrate the underlying
wood 3/4 inch. Example: 1/2-inch drywall plus 3/4-inch
penetration requires a 1 1/4-inch nail. A longer nail does
not fasten more securely than one properly sized, and
the longer nail is subject to the expansion and
contraction of a greater depth of wood.
Smooth-shank, diamond-head nails are commonly
used to attach two layers of drywall; for example, when
fireproofing a wall. Again, the mil length should be
selected carefully. Smooth-shank nails should penetrate
the base wood 1 inch. Predecorated drywall nails, which
may be left exposed, have smaller heads and are
color-matched to the drywall.
SCREWS. Drywall screws (fig. 5-3, view B) are
the preferred method of fastening among professional
builders, cabinetmakers, and renovators. These screws
are made of high-quality steel and are superior to
conventional wood screws. Use a power screw gun or
an electric drill to drive in the screws. Because this
method requires no impact, there is little danger of
jarring loose earlier connections. There are two types of
drywall screws commonly used: type S and type W.
Type S. Type S screws (fig. 5-3, view B) are
designed for attachment to metal studs. The screws are
self-tapping and very sharp, since metal studs can flex
away. At least 3/8 inch of the threaded part of the screw
should pass through a metal stud. Although other lengths
are available, 1-inch type S screws are commonly used
for single-ply drywall.
Type W. Type W screws (fig. 5-3, view B) hold
drywall to wood. They should penetrate studs or joists
at least 5/8 inch. If you are applying two layers of
drywall, the screws holding the second sheet need to
penetrate the wood beneath only 1/2 inch.
TAPE. Joint tape varies little. The major
difference between tapes is whether they are perforated
or not. Perforated types are somewhat easier to bed and
cover. New self-sticking fiber-mesh types (resembling
window screen) are becoming popular. Having the mesh
design and being self-sticking eliminates the need for
the first layer of bedding joint compound.
JOINT COMPOUND. Joint compound comes
ready-mixed or in powder form. The powder form must
be mixed with water to a putty consistency.
Ready-mixed compound is easier to work with, though
its shelf life is shorter than the powdered form. Joint
compounds vary according to the additive they contain.
Always read and follow the manufacturers
specifications.
ADHESIVES. Adhesives are used to bond
single-ply drywall directly to the framing members,
furring strips, masonry surfaces, insulation board, or
other drywall. They must be used with nails or screws.
5-4