Static field route #19358

What do I do when flat-oval duct seams split from heat expansion?

Spiral, Round & Oval Duct Install⚠️ CHECK BEFORE YOU FIXField answer expansion

📖 Verified core answer

Thermal movement needs somewhere to go. Replace the damaged section and add the approved expansion/flexible detail if the run is growing under heat.

Open in Field Rescue Open category

Field verification checklist

Inspect how long the seam split is and whether the duct is distorted.
Check if the run is hard-fixed at both ends.
Look for missing expansion allowance or over-rigid supports.
Verify material/gauge/temperature requirement.
Coordinate approved expansion joint or replacement.

Ask foreman

The flat-oval seam at [location] has split open on the warm discharge run. I checked fixed points and heat movement. Do you want this section replaced and expansion detail added?

Text to foreman

Route options

ACorrect it only if the fix is within your assignment and approved method.

BHold and document if it affects pressure class, listed assembly, material spec, support load path, fire barrier, equipment, TAB, or another trade.

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

Do not do this

Do not smear sealant over a split structural seam and keep the run locked solid.

Why this matters

Thermal seam failure can keep reopening, leak air, and damage supports if movement is not handled.

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, pressure/material schedule, and AHJ/code requirements.

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