There are as many base feet in a cripple rafter as there are number of feet on the plate from the corner of the hip to the corner or center of the valley rafter. (See rules for base, fig. 21.)

To obtain the length of a cripple rafter, lay the square on the rafter at the base and rise of the common rafter as many successive times as there are base feet in the rafter. (See figs. 30 and 32.) Mark on the rise for the hip and valley cuts. To obtain the face cut to meet the hip rafter, use the same rule given for the jack rafter that meets the hip. (See fig. 35.) For the lower cut of the cripple rafter to meet the valley use the same rule as for the face cut to meet the hip, only reverse the angular cut by marking across the rafter, and cut parallel to the hip cut. (See fig. 36.)

Cripple Rafters 38

Fig. 36