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Successful construction in the military TO demands a thorough familiarity
with the materials used and
the planning required to assemble these materials into a building—a
building that is most suitable for the
requirements, while most effectively fitting within the constraints imposed
by the locality. This chapter
acquaints the carpenter with those materials and with planning techniques.
PLANNING
The importance of properly planning construction cannot be overemphasized.
Construction planning
allows an orderly series of operations and prevents duplication of effort
and waste of materials. The
major considerations in planning are--
· The construction-plant layout.
· The distribution of materials.
· The number of skilled and semiskilled men available.
· The number and type of units to be constructed.
From a list of the operations required, an estimate is made of the total
number of man-hours needed. This
estimate forms the basis for determining the number and type of men needed
and for organizing the
erection crew(s). (Refer to Appendix C.) Arrangements for assembling the
necessary materials at the job
site and for the preliminary cutting and assembly are made in advance.
The method of erecting buildings directly influences the amount of time,
labor, and materials needed. The
methods may be divided into two types: the built-in-place method and the
panel, or preassembly
(prefabricated), method. Working parties for both methods should be set
up as follows:
· The layout party.
· The cutting party.
· The assembling party (built-in-place method only).
· The carrying party.
· The erecting party for sidewalls.
· The erecting party for rafters.
· The sheathing party (built-in-place method only).
· The roofing party.
· The door-and-window party.
· The finishing party.
BUILT-IN-PLACE METHOD
In this method, each piece is separately erected in its proper place.
When using the built-in-place method,
the noncommissioned officer in charge (NCOIC) of construction divides
the men into working parties,
whose duties may be as follows:
· Laying out the foundation.
· Grading and excavating.
· Laying out and cutting various sizes of material.
· Carrying material to the cutting and erecting parties.
If a party finishes its task before the building is completed, it is
assigned a new task. For example, if the
party laying out the foundation completes its work before erection of
the building has begun, it is
assigned a new duty (such as
cutting rafters).
Parts of the building are built in the
following order: footings, posts,
sills, joists, floor, soles, studs,
plates, girts, rafters, bracing,
siding, sheathing, roofing, doors,
windows, steps, and inside finish
(if used).
PANEL METHOD
In this method (also called preassembly (prefabricated)), a complete
section is built as a unit and then set in the building in its proper
place. It is used extensively because it makes for greater speed, better
control over working parties, and better use of manpower. For example,
it allows the use of a standard list of sizes for each similar section.
Standard plans shown in Technical Manuals (TMs) 5-02-1 and 5-302-2 further
simplify construction. The panel method requires careful planning before
the actual construction. Before measuring and cutting lumber, the number
and size of sections that are alike should be determined from the construction
drawing. This ensures availability of the correct numbers of each piece.
The carpenter assigns a crew to cut and assemble one section. (Several
cutting and assembling parties
may be used at one time on different types of sections.)
In most cases, a template (Figure 2-1) is built as a guide for assembling
the section. The template should
be built square and should be correct in size.
The number and size of each piece in a section are given to the man
in charge of the cutting party. The
cutting party cuts the timber to the correct length with a handsaw or
power saw. The length is measured
with a square and a tape. After one piece has been cut, it may be used
as a pattern for marking the
remaining pieces (Figure 2-2). The pattern is set up by nailing two blocks
to the piece of correct size, one
near each end, as shown in the figure. These blocks act as stops to hold
the pattern in place on the timber
to be marked.
The plate and sole are placed
in the template with the studs
and girts between them; then
the door and window posts, if
any, are placed as shown in
Figure 2-1. The girts, sole,
and plate are nailed to the
studs with 16d or 20d nails. If
insulation board is used, it
and the wall sheathing are put
on the section before it is taken out of the template. Applying the wall
finish before raising the section makes the use of scaffolds or ladders
unnecessary.
The erecting party sets the sections into place, braces them temporarily,
and nails them together. The end
section should be first; it may be erected on graded earth. The sidewall
sections are next; they should be
erected so as to keep the two walls even. The rafter party can then place
the rafters on the walls.
The panel method of erection may be used for all types of small buildings
and large warehouses. When
this method is used for large buildings, cranes are used to place sections
too heavy to be handled by hand.
WARNING: When machinery is used, use caution in fastening the
lifting cable or rope to avoid
damaging the section.
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