PURLINS & EAVE STRUT

Purlins are a horizontal structural membrane in a roof. It helps in supporting the loads from the roof deck and are properly supported by the building wall or principal rafter. These roof purlins are extensively used in large sized roofing platforms, factory, workshops, godowns and many industrial sheds.

In steel construction, the term purlin typically refers to roof framing members that span parallel to the building eave, and support the roof decking or sheeting. The purlins are in turn supported by rafters or walls. Purlins are most commonly used in Metal Building Systems, where Z-shapes are utilized in a manner that allows flexural continuity between spans.

It is the practice in the steel industry that structural shapes are assigned representative designations for convenient shorthand description on drawings and documentation: Channel sections, with or without flange stiffeners, are usually referenced as C shapes; Channel sections without flange stiffeners are also referenced as U shapes; Point symmetric sections that are shaped similar to the letter Z are referenced as Z shapes. Section designations can be regional and even specific to a manufacturer. In steel building construction, secondary members such as purlins (roof) and girts (wall) are frequently cold-formed steel C, Z or U sections, (or mill rolled) C sections.

Cold formed members can be efficient on a weight basis relative to mill rolled sections for secondary member applications. Additionally, Z sections can be nested for transportation bundling and, on the building, lapped at the supports to develop a structurally efficient continuous beam across multiple supports.

p13

C Purlins C Purlins are horizontal structures that are used to support the load from the roof deck or the sheathing. The plane surface of this purling on one side has made it a preferred material for... More Info

p13

C Purlins C Purlins are horizontal structures that are used to support the load from the roof deck or the sheathing. The plane surface of this purling on one side has made it a preferred material for... More Info


p13

Z Purlins Z Purlins are made using cold-formed or rolled sheets for supporting roof. The flexible shape of these beams facilitates various designs solutions. These purlins are extensively used in hug... More Info

p13

Z Purlins Z Purlins are made using cold-formed or rolled sheets for supporting roof. The flexible shape of these beams facilitates various designs solutions. These purlins are extensively used in hug... More Info


p13

The third type of secondary structural members, after purlins and girts, is the eave strut. This unique structural element is located at the intersection of the roof and the exterior wall, so that it ... More Info