8 inches and also in sizes of 3/4 by 8 inches and 3/4 by
10 inches. “Anzac” siding is 3/4 by 12 inches in size.
Usually, the finished width of bevel siding is about
one-half inch less than the size listed. One side of
beveled siding has a smooth planed surface, whereas the
other has a rough resawn surface. For a stained finish,
the rough or sawn side is exposed because wood stain
works best and lasts longer on rough wood surfaces.
DOLLY VARDEN.— Dolly Varden siding is
similar to true bevel siding except that it has shiplap
edges. The shiplap edges have a constant exposure
distance (fig. 4-1). Because it lays flat against the studs,
it is sometimes used for garages and similar buildings
without sheathing. Diagonal bracing is therefore needed
to stiffen the building and help the structure withstand
strong winds and other twist and strain forces.
DROP SIDING.— Regular drop siding can be
obtained in several patterns, two of which are shown in
figure 4-1. This siding, with matched or shiplap edges,
is available in 1- by 6-inch and 1- by 8-inch sizes. It is
commonly used for low-cost dwellings and for garages,
usually without sheathing. Tests have shown that the
tongue-and-grooved (matched) patterns have greater
resistance to the penetration of wind-driven rain than the
shiplap patterns, when both are treated with a
water-repellent preservative.
Fiberboard and Hardboard
Fiberboard and hardboard sidings are also available
in various forms. Some have a backing to provide
rigidity and strength, whereas others are used directly
over sheathing. Plywood horizontal lap siding, with a
medium-density overlaid surface, is also available as an
exterior covering material. It is usually 3/8 inch thick
and 12 or 16 inches wide. It is applied in much the same
manner as wood siding, except that a shingle wedge is
used behind each vertical joint.
A number of siding or paneling patterns can be used
horizontally or vertically (fig. 4-1). These are
manufactured in nominal 1-inch thicknesses and in
widths from 4 to 12 inches. Both dressed and matched
and shiplapped edges are available. The narrow and
medium-width patterns are usually more satisfactory
under moderate moisture content changes. Wide
patterns are more successful if they are vertical-grained
(to keep shrinkage to a minimum). The correct moisture
content is necessary in tongue-and-groove material to
prevent shrinkage and tongue exposure.
Figure 4-2.-Vertica1 board siding.
Treatment
Treating the edges of drop, matched, and shiplapped
sidings with water-repellent preservative helps prevent
wind-driven rain from penetrating the joints exposed to
the weather. In areas under wide overhangs or in porches
or other protected sections, the treatment is not as
important. Some manufacturers provide siding with this
treatment already applied.
Applications
A method of siding application, popular for some
architectural styles, uses rough-sawn boards and battens
applied vertically. These can be arranged in three ways:
board and batten, batten and board, and board and board
(fig. 4-2).
Sheet Materials
A number of sheet materials are now available for
use as siding. These include plywood in a variety of face
treatments and species, and hardboard. Plywood or
paper-overlaid plywood, also known as panel siding, is
sometimes used without sheathing. Paper-overlaid
plywood has many of the advantages of plywood
besides providing a satisfactory base for paint. A
medium-density overlaid plywood is not common. Stud
spacing of 16 inches requires a minimum thickness of
panel siding of three-eighths inch. However, 1/2- or
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