In Pre-Engineered Buildings (PEB), Z and C purlins play a critical role in supporting the roof and wall systems, forming the backbone of secondary framing. These cold-formed members are designed to efficiently transfer loads from sheeting to the main structure, while maintaining a lightweight and economical system. Why Z & C Purlins Matter Efficient load distribution from roof and wall panels Lightweight design reduces overall structural weight Z purlins allow lapping, improving continuity and strength C purlins are typically used for end bays and simple spans