SECONDARY FRAMING SYSTEM
Secondary framing consists of elements which support the roof and wall sheeting and transfer load to the primary framing. These include Roof Purlins, Wall Grits, Eave Struts, and Clips etc.
Roof Purlins
Roof purlins are cold-formed C & Z profiles, normally 150 to 250 mm deep out of 1.6 to 3.15 mm thick steel. These are fixed to the top flanges of rafters by means of clips bolted to the rafters and the purlin web bolted to the clips. Purlin ends overlap to act as conditions beam.
Wall Girts
Wall girts are cold-formed C&Z sections, normally 150 to 250mm deep out of 1.6 to 3.15 mm thick steel. These are fixed to the top flange of the side wall columns. There are two types of fixations: Fixed to the outer flange of the side wall columns by means of clips bolted to the column and girt web bolted to the clips Overlap connections are provided for continues beam action. Endwall girts and flush girts on side walls are normally flushed to the outer flange of the columns by means of clips which are bolted to the clips.
Eave Struts
Eave struts are C profiles or Z profiles, normally 200 to 250 mm deep out of 2 to 3.15 mm thick steel. These are fixed to the outer flange of the side wall columns by means of clips bolted to the column and eave strut bottom flange bolted to the clip. Roof purlins also act as wind struts and enable transfer of strut load to the side wall columns through adequate bracing.