ANSWER TO REVIEW QUESTION 1
Plan and elevation drawings are classed as general drawings, while sections and detail views comprise
detail drawings. A floor plan would be a general drawing. (para 2-1, a)
ANSWER TO REVIEW QUESTION 2
On an elevation drawing, the centerline symbol is used to indicate finished floor lines. (para 2-4, b)
Section II. Light and Heavy Wood Framing
2-6.
WOOD CONSTRUCTION
(b) Douglas fir. Douglas fir in the
Wood is a basic construction material used
form of lumber and timber is one of the most
widely by the military, particularly in theater of
desirable woods for structural purposes. It also has
operations (TO) buildings. Therefore, you should be
extensive use as poles, piling, and ties, and large
familiar with the classification and grading of wood
quantities are cut into veneer for plywood and other
(lumber). The specific type and cut of lumber to be
purposes. Douglas fir is strong, moderately hard, and
used in a construction is given in the associated
heavy. In general, however, it has a tendency to
specifications.
check and split and does not hold paint well.
a. Species. Native species of trees are divided
into two classes: hardwoods, which have broad
graded by different standards.
Only softwood
leaves; and softwoods, which have leaves like
grading is considered here because, as explained
needles or scales. No definite degree of hardness
previously, hardwoods are rarely used for structural
divides the species. In fact, some hardwoods actually
purposes.
are softer than an average softwood.
(1) Grading criteria. In most cases, the
Some familiar native
grade of lumber is based on the number, character,
(1) Hardwoods.
species of the hardwood or deciduous class are ash,
and location of features, such as knots and pitch
birch, hickory, oak, beech, and maple. All are broad-
pockets, which are commonly called defects and
leaved. Lumber cut from hardwoods is not generally
defined as any irregularity occurring in or on wood
used for the construction of structural framing but is
that may lower its strength, durability, or utility
employed principally for flooring, special interior
value. The best grades are practically free of these
paneling, trim, and doors.
features; others, comprising the greater bulk of
lumber, contain fairly numerous knots and other
(2) Softwoods. Most native species of
natural growth characteristics.
softwood bear cones and are called coniferous
woods. Some familiar softwoods are pine, spruce,
(2) Select lumber. Select lumber is the
fir, cedar, and redwood. These woods are worked
general classification for lumber of good appearance
easily and make suitable material for structural
and finishing qualities. Grades A and B are suitable
framing. Of the various softwoods, southern yellow
for natural finishes and grades C and D for paint
pine and Douglas fir are the varieties used most
frequently for construction.
(3) Common lumber. Common lumber is
All
the general classification for lumber containing the
(a) Southern yellow pine.
southern yellow pine used for structural purposes is
defects and blemishes described above. The grades
classified as longleaf or shortleaf. The wood is
are numbered 1 through 5. Grades No. 1 and 2 are
dense, moderately hard, and strong. When described
for use without waste in framing and sheathing; No.
in a bill of material or specifications, longleaf yellow
3 can be used for temporary construction; and No. 4
pine is abbreviated as LLYP, and shortleaf yellow
and 5 are not generally used in construction
pine as SLYP.
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