Static field route #19318

What do I do when a heavy duct is hung from an open-web joist bottom chord?

Seismic Bracing, Sway Control & Structural Coordination⛔ STOP / GET DIRECTIONField answer expansion

📖 Verified core answer

Do not put heavy point loads on a joist chord without approved structural direction. Hold the load and move to an approved distributed support detail.

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Field verification checklist

Identify exactly what member is carrying the load.
Look for twisting, bowing, weld cracks, or strap movement.
Check structural/hanger drawings for approved joist loading.
Temporarily support duct before moving hangers.
Do not resume until the load path is approved.

Ask foreman

This heavy duct/plenum is being carried by the open-web joist bottom chord at [location]. I see the steel twisting. Do you want us to hold and get an approved bridge/panel-point support detail?

Text to foreman

Route options

AMake the field correction only if it is within your assignment and the approved method.

BHold and document the condition if the fix affects support load path, structural steel, seismic restraint, life safety, another trade, or inspection.

CBring the foreman/detailer the location, what you checked, and what decision you need before loading, cover, startup, or rework.

Do not do this

Do not wrap heavy duct straps around random joist chords or web members.

Why this matters

Wrong joist loading can damage the roof/floor structure and trigger serious inspection and safety issues.

Final verification

Use this as field training guidance. Final direction still comes from the foreman, approved drawings, project specs, manufacturer installation instructions, employer safety policy, structural/seismic detail, and AHJ/code requirements.

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