Open Truss Roof Structure

The simplest form of a truss is one single triangle.

Open truss roof structure.

Components of roof truss. A roof truss is supported by the exterior walls and span the width of the building. In most truss members only flexural buckling of the compressed members in the plane of the truss structure and out of the plane of the truss structure need be evaluated. In essence a roof built on trusses is much more structurally sound.

Trusses are gradually replacing the conventional rafters to the point that nowadays more than 80 percent of new residential construction uses trusses to support the roof. Rafters have a tendency to flatten under gravity thrusting outwards on the walls. This type of truss is seen in a framed roof consisting of rafters and a ceiling joist and in other mechanical structures such as bicycles and aircraft. Because of the stability of this shape and the methods of analysis used to calculate the forces within it a truss composed entirely of triangles is known as a simple truss.

A timber roof truss is a structural framework of timbers designed to bridge the space above a room and to provide support for a roof trusses usually occur at regular intervals linked by longitudinal timbers such as purlins the space between each truss is known as a bay. The benefit of a truss over older structural designs like coupled rafters is that it provides longitudinal support. Roof framing has undergone a quiet revolution over the past half century.