Fig. 41. Showing Relative Position of Plates in Roof
with Two Unequal Pitches.
Fig. 42. Method of Finding Bevels for Purlins
in Equal-Pitch Roofs.
In [Fig. 42] is shown a very simple method of finding the bevels for purlins in equal-pitch roofs. Draw the plan of the corner as shown, and a line from m to o; measure from o the length x y, representing the common rafter, to w; from w draw a line to m; the bevel shown at 2 will fit the top face of the purlin. Again, from o, describe an arc to cut the seat of the valley, and continue same around to S; connect S m; the bevel at 3 will be the side bevel.