What is a purlin in construction?

A purlin in construction refers specifically to a horizontal support structure that is used to span rafters in a roof system. It is typically placed perpendicular to the rafters and serves the vital function of providing additional support for the roof covering, such as metal sheets or shingles. Purlins are essential in distributing the load of the roofing materials evenly across the rafters, thus enhancing the stability and strength of the roof structure.

This configuration allows for better load management and can be essential in ensuring that the overall structure can withstand various stresses, such as those caused by wind or snow loads. The use of purlins aids in creating a stronger roof framework, making them an integral part of many building designs, particularly in commercial and industrial construction.