The Steel Joist Institute (SJI) Code of Standard Practice (Code or COSP) for steel joists and Joist Girders establishes trade practices for the steel joist and Joist Girder industry. The practices presented in the COSP are “in accordance with good engineering practice, tend to ensure safety in steel joist and Joist Girder construction, and are standard within the industry” (Section 1.1). Unlike the AISC Code of Standard Practice, the SJI COSP is not a comprehensive summary of acceptable practices for all involved parties, including the fabricators, erectors, structural engineers, owners and general contractors or construction managers. Rather the SJI COSP is focused primarily on the characteristics and properties of joists and Joist Girders themselves and the structural engineer’s responsibilities in properly specifying them for the purposes of design, bidding and installation.

The specification of joists and Joist Girders can provide an economical structural solution, but there are very specific requirements that must be understood by all parties. The 2020 SJI COSP provides a practical approach to specifying joists, to introduce design terms for use by the structural engineer, and to identify and clarify topics that may have been subject to varying interpretation in the past. This commentary provides observations and analysis of specific aspects of the COSP that have a direct impact on the structural engineer’s practice of specifying steel joists. A familiarity and understanding of the entire SJI COSP is necessary to ensure the proper design and documentation of steel joists and Joist Girders. However, the following discussion highlights sections of particular interest to the specifying structural engineer.