One dimension of these pieces is always governed by the width of the studding. When 4-inch studding is used the posts may be 4x6 or 4x8 inches, the girts 4x8 inches and the braces 3x4 inches. For wider studding the thickness of the posts and girts must be the same as the width of the studding. The posts at interior angles should always be 2 inches wider in one dimension than in the other to give a nailing for the sheathing.
The connection of the girts with the post should be made as shown in Fig. 22, and the braces should be mortised and pinned as shown in Fig. 23, although they are too often merely spiked. All pins used in framing should be made of hard wood and should be 7/8 inch diameter for girts and ¾ inch for braces.
When the attic floor joists come a short distance below the plate they are usually supported on a 1x7 board, called a "ledger board," "ribbon" or "false girt," let into the studding, as shown in Fig. 20. When there is a wide opening in the second story, however, a solid girt must be substituted, as shown in Fig. 19, to provide sufficient strength to support the floor and roof. Where there is room, it is desirable to truss over all openings exceeding 4 feet in width.
Plate. - If the attic joists rest on top of the plate, then the plate cannot be wider than the studding unless it projects on the outside, but if the plate is above the attic joist, as in Fig. 20, a wider plate may be used, say 4x6 inches; the wider the plate the greater is the resistance offered to the thrust of the rafters and the consequent springing of the wall. Whatever size is used, it is better to build the plate up out of pieces 2 inches thick, spiked together, than to use solid timber, as the built up plate will warp or twist less and can be more strongly spiked, and the joints more firmly spliced.
45. Laying Out, - The framing of the outside walls of a wooden building is generally shown by a set of elevation drawings showing each side of the building in the manner illustrated in Fig. 19. In making these drawings the draughtsman will find that the work can be more easily and quickly done by drawing them on the dull side of tracing cloth or paper laid over the finished elevations. The sills, posts, girts and plates should first be drawn, then the studding framing the door and window openings, next the braces and lastly the filling in studding. The latter are often indicated by a single line.
The sizes of all special timbers should be carefully marked on the drawings, and the location of the centre of all openings should be given. The size and height of the window openings is best designated by giving the size of the glass and the height of the finished stool above the floor, as shown in Fig. 19. The height of the plates and girts should also be correctly given, and the pitch of the roof in terms of rise to run.
■ In locating the braces it should be remembered that a brace is most effective when at an angle of 45 °, and should be connected with the post at from one-third to one-half the height of the story. Every dimension necessary for the complete construction of the frame should be found on the framing drawings.
No drawings that an architect has to make require greater thought and exactness than the framing plans, for upon them depend the proper construction of the building and often its safety, and moreover any error in the figures generally leads to considerable expense through waste of material and labor, and for any such expense the architect is in most cases responsible.