What is 'purlin' and its function in a roofing system?

Purlins are essential components of a roofing system, serving as horizontal supports that provide structural reinforcement for roofing panels. They are typically installed parallel to the eaves and help distribute the load of the roof sheathing or roofing material across the underlying framework, which can include rafters or trusses. By providing this support, purlins help maintain the overall integrity and stability of the roof structure, enabling it to bear various loads, such as snow, rain, and wind pressure.

In addition to their structural role, purlins also create spaces that allow for insulation and ventilation, contributing to the overall performance and energy efficiency of the building. Their placement and size can vary based on the roofing material used and the design requirements, but their fundamental purpose in supporting and stabilizing the roofing system remains consistent across different applications. This understanding of purlins as vital horizontal supports clarifies their importance in construction and design.