Static field route #19320

What do I do when a trapeze is clamped to a diagonal joist web member?

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

📖 Verified core answer

Do not hang a duct trapeze from a diagonal joist web member unless the structural detail specifically allows it. Move the load to an approved support point.

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Field verification checklist

Confirm whether the clamp is on web, chord, beam, or bridging.
Look for bowed web steel or clamp slip.
Check structural notes and hanger detail.
Temporarily support duct before removing the bad hanger.
Coordinate if the approved point conflicts with other trades.

Ask foreman

The trapeze at [location] is clamped to a diagonal open-web joist member and it is bowing. Do you want us to shift to an approved chord/panel point or engineered bridge?

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 side-load joist web rods because they are nearby and convenient.

Why this matters

Wrong structural loading can bend joists, fail inspection, and create overhead support failure risk.

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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