Open Truss Roof Structure

Components of roof truss.

Open truss roof structure.

The benefit of a truss over older structural designs like coupled rafters is that it provides longitudinal support. 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. A roof truss is a structural framework of timbers designed to bridge the space above a room and to provide support for a roof. 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.

Rafters have a tendency to flatten under gravity thrusting outwards on the walls. A roof truss is supported by the exterior walls and span the width of the building. 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 simplest form of a truss is one single triangle.

Roof framing has undergone a quiet revolution over the past half century. 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. 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.