Nails, Screws, Bolts, and Other Fasteners - Carpenter's and Builder's Math, Plans, and Specifications - page 33

Fasteners for Plaster or Drywall
Because of the relatively fragile nature of plaster and drywall in
comparison to brick, stone, and concrete, fasteners used with the
former must necessarily be different from those used with the lat-
ter. Whenever weight of any consequence is involved, or a direct
outward pull is to be exerted, a fastening is best accomplished with
standard wood screws or lag screws inserted through the object to
be fastened and driven through the plaster or drywall directly into
the studs, rafters, or other framing material beneath. When this is
impossible, anchor directly to the plaster or drywall with one or
more of the fastening devices discussed in the following sections.
Expansion Anchors
Metal expansion anchors are unsuitable for use with plaster or gyp-
sum board because they tend to crush the walls of the hole into
which they are inserted, and then fall or pull out easily (assuming
they can be tightened in place to begin with). Plastic expansion an-
chors (see Figure 1-28) are better in this regard, perform their best
with radial loads, and are the poorest of any anchor on axial loads.

A

B C

D

Figure 1-28 Expansion anchors: (A) made from lead alloy for
use with lag screws, (B) made from a softer lead alloy for use
with wood screws, (C) made from plastic and best used with
sheet-metal screws, and (D) made from fiber-jacketed lead—a
plug-type anchor sized here for small wood screws.