Purlins are horizontal structural elements in roof assemblies of steel-framed buildings. They are positioned between roof coverings and principal rafters or trusses, supporting the roofing sheets. Employed widely in pre-engineered buildings (PEBs), purlins are typically made of cold-formed steel. They exist in two principal forms, Z-purlins, which are recognized for their overlapping toughness, and C-purlins, which are best suited to shorter spans. While frequently covered up from sight, purlins play a crucial role in contemporary steel structures' performance, stability, and effectiveness.