Secondary Structural Framing

Purlins, girts and eave struts are secondary structural members used to support the wall and roof panels. Purlins are used on the roof; girts are used on the walls and eave struts are used at the intersection of the sidewall and the roof.

Secondary members have two other functions: they act as struts that help in resisting part of the longitudinal loads that are applied on the building, such as wind and earthquake loads.And they provide lateral bracing to the compression  flanges of the main frame members, thereby increasing frame capacity.

 

Secondary Structure


• Cold-Formed "Z" Sections
• Cold-Formed "C" Sections
• Eave Strut Section
• Secondary Framing Details

Purlins, girts and eave struts are available in two standard surface finishes and in six standard thicknesses as shown in the table below:

cxccc


Standard Material
Surface finish

Specifications
(equivalent to)

Available Thickness (mm)

Purlins/Girts

Eave Struts

Z-Sections

C-Sections

 Red Oxide (Primer)

ASTM A607
Grade 50

1.5, 1.75, 2.0,
2.25, 2.5, 3.0

2.0, 2.5, 3.0

2.0, 2.5

 Pre-Galvanized

ASTM A653
Grade SS50, Class I

1.5, 1.75, 2.0,
2.25, 2.5

2.0, 2.5

2.0, 2.5