Method of erecting a roof structure

Abstract

A roof structure made up by a plurality of truss members interconnected by purlins which carry sheet metal roofing material. The truss members are made up of a top compression member which is preferably a tube and a bottom tension tube the members being connected together by vertical tension struts and joined at their ends. The top compression member of each truss consists, before erection of a straight or partially curved member and the bottom tension tube of a downwardly bowed tube. The structure is given form and rigidity by passing high tension steel cables through the bottom tension tubes and, after the purlins and sheet metal roofing material have been attached, tensioning them to bring the top compression members to an upwardly curved configuration and the bottom tension tube to a straight or slightly upwardly bowed form.

Dependencies are inferred from the claim text.