Pitched Roof Trusses

Roof trusses are engineered wood alternatives to hand framed rafters.

Pitched roof trusses. A pitched roof uses not only the external wall systems but also particular parts of the internal walls. Pre manufactured stock trusses are constructed with spruce pine fir spf or southern yellow pine syp lumber. They support live and dead loads by efficiently transferring the loads to the building walls or supports. The pitched or common truss is characterized by its triangular shape.

A howe scissors truss is so called because its appearance resembles that of an opened pair of scissors. A pitched roof construction is the classic old school way of roof construction. These trusses the meet building code criteria as specified by structural building components of america sbca and the truss plate institute tpi. Some common trusses are named according to their web configuration such as the king post fan fink or howe truss.

A cut roof this is the traditional method of cutting the timber on site and building up the roof using rafters ridge boards joists and purlins etc the exact details being determined by the size of roof size of timbers etc. The chord size and web configuration are determined by span load and spacing. They are designed at a 4 12 pitch to be spaced 2 foot on center. It is most often used for roof construction.

With rafters collars ties struts ridges underpurlins ceiling joists hanging beams combination hanging and strutting beams pitching plates and so on. Its bottom chords join together at the apex creating a pitched or vaulted ceiling. Examples of live loads are snow wind rain and temporary construction loads.