ANSWERS TO SELF TEST
The bearing strength of stud walls is determined by the strength of the studs (para 2-1).
A stud called a "T-post" is used wherever a partition meets an outside wall. This member provides a solid
nailing base for the inside wall finish (para 2-1b).
Studs may be placed 4 feet apart if girts are used (para 2-1d(1)).
The walls must be plumbed and straightened after the corner posts, T-posts and intermediate studs have been
nailed to the plates and the girts but before the permanent braces and rafters have been installed (para 2-2).
Internal diagonal bracing is used when no interior finish is planned (para 2-3d).
Gable roofs are most commonly used by the Army because they are simple to design, economical to
construct, and may be used on any type of structure (para 2-4a).
3/9 = x/12; 9x = 36; x = 4. Therefore, you would have 4 inches of rise per foot of run (para 2-4e).
Total run is one-half the span distance, which was given as 20 ft 6 in. Therefore, total run in this case is 10 ft
3 in (para 2-4f(1)(3)).
Rafters, ridge boards, and plates are the three principal members of a roof frame (para 2-5b).
Bowed rafters should always be installed with the bow up (para 2-6b(2)).
24 / 2 = 12 feet total run. On figure 2-17 find the run-rise line for 12 run - 6 rise. Move to right to 12 on
main scale and read 13 ft 5 inches for rafter length (para 2-6d(3)).
Collar beams are horizontal ties between two rafters placed somewhere between the roof ridge and the top
plate. The nearer they are to the top plate the better they perform their main function, which is to prevent the
building walls from spreading. This type of bracing is used in the roofs of small buildings where no ceiling
joists are used (para 2-7).
The primary function of the rafters is to carry the roof loads to the studs (para 2-8b(1)).
The trussed rafter system permits use of smaller size lumber and more economical use of manpower (para 2-
When trussed rafters are used, the ridge board is eliminated (para 2-8d).
Knee braces may be installed on each rafter truss if severe winds are anticipated, and may be spaced as
widely as 16 feet on centers where wind is not a serious problem (para 2-8e).
A compression member requires a greater sectional area for a given stress than does a tension member (para