Although cantilever trusses of wood are not often used, conditions sometimes exist, as in the case of a wide centre-span with shorter spans on each side, where a cantilever truss will meet the requirements better than any other type.

Fig. 62.

Fig. 62 shows a simple cantilever trussed roof, suggested by Mr. John Beverly Robinson in an article advocating the use of the cantilever in building construction, published in the "Engineering Magazine" for November, 1896, which is feasible for wooden construction.

Fig. 63.

Fig. 63* shows an "open center barn," in which the roof is supported on the cantilever principle, the posts and braces being from 8 to 10 feet, on centers.

Cantilever trusses when supporting a roof over a central span must be used in pairs, the truss on one side being independent of that on the other.

The principle of the cantilever truss is explained in Chapter II (Foundations On Compressible Soils)., Section 43.

♦This cut was suggested by one contributed to "Carpentry and Building" by a carpenter who designed and built a barn In this manner. The sketch la Intended to show the application to either a curb roof or one with straight pitch.