HIP ROOF FRAMING We have already referred to the great variety of problems—many of them of considerable com plexity, depending on the greater or less com plexity of the kind of roof selected for the struc ture—that arise when the carpenter is con fronted with the problem of putting on the roof. These problems will vary with the number of hips and valleys, the pitch, length of run, etc., but the fundamental principles involved in their solution are not many; and a familiarity on the part of the carpenter with the steel square will enable him to solve them all.
Side Cut of the Hip.—In connection with the hip there must be another cut considered, called the side cut of the hip, though the angle to obtain this cut is across the top or back of the rafter. Were there no slope to the roof, this
angle where it meets the ridge pole would be an angle of 45 degrees, but when a slope is given this angle becomes more acute. The rule is, take the length of the hip on the blade and its run on the tongue, the blade gives the cut or take 17 on the tongue and 18i on the blade, blade gives the cut as shown in Fig. 41.
Beveling of Hip Rafter.—The hip-rafter should be beveled so as to be in plane of the common rafter; height of hip on tongue, length of hip on blade; tongue gives bevel, or we take 8 on tongue, 18-1 on blade; tongue gives bevel, as shown in Fig. 42. These figures will cover all cuts in putting on cornice and sheathing.
To Cut Planceer, to Run Up Valley: Take height of the common rafter on tongue, length of rafter on blade; tongue gives the miter cut. The side cut takes the length of common rafter on blade, and run on tongue; tongue gives cut.
These figures give the cuts regardless of width of building.
Fig. 43 applies to backing of hips where the corner is at right angles and the pitches are the same. At the angle D will be seen the inter section of the sides of the angle rafter with the sides of the plan.
With one point of the compasses at D, de scribe the curve from the line as shown. Tan gential to the curve draw the dotted line, cutting All, then draw a line parallel to A B, the pitch of the hip. The bevel will be found at C, which is a section of the hip-rafter.
The Principles to Be Determined in a Hip Roof are eight, namely: 1st. Span or width of building to be roofed. 2d. Run of the building, which is / the span. 3d. The rise given the common rafter.