Mastering Steel Joists
Mastering Steel Joists
Welcome to the interactive detailer's handbook for SJI (Steel Joist Institute) Standard specifications. Steel joists are open-web steel trusses used primarily as secondary framing members to support floors and roof decks. This tool allows you to explore standard series, check design parameters, and calculate requirements instantly.
Design Perspective
Understand economy, depth-to-span ratios, and specific loading conditions like snow drifts or net uplift.
Detailing Rules
Access quick references for bearing depths, bridging requirements, and end anchorage standards.
Technical Data
Interactive charts comparing K, LH, and DLH series capabilities to select the right member.
Standard Joist Series
Explore the four primary categories of SJI joists.
K-Series Joist
StandardSpecifications
Detailer Notes
The "workhorse" of the industry. Designed for simple spans with uniform loads.
Design & Performance Data
Comparative analysis of span capabilities and depth efficiencies.
Span Capabilities by Series
Economical Depth Ranges
Detailer's Handbook
Standard dimensions and SJI requirements for construction documents.
Standard Bearing Depths (Seat)
Seat depth is critical for establishing Top of Steel (T.O.S.) elevations.
- K-Series 2.5"
- LH-Series 5.0"
- DLH-Series (Chords < #18) 5.0"
- DLH-Series (Chords > #19) 7.5"
Bridging Standards
Ensures lateral stability during erection and service.
Standard for K-series; continuous angles welded to top and bottom chords.
Crossed angles; required for LH/DLH stability and uplift conditions.
End Anchorage Requirements
Standard Camber Logic
Joists are manufactured with an upward curve to offset dead load deflection.
Camber is provided on all LH and DLH series, and K-series over 20' span.
Note: Excessive camber can lead to uneven floor slabs; verify T.O.S. at mid-span.