Static field route #19601

What do I do when a storm drain pipe crosses the path of a duct run that needs a 45-degree offset?

Coordination, Clashes, Sequencing & Rework🚨 STOP / VERIFYField answer expansion

📖 Verified core answer

Do not notch, flatten, or compress the duct around a plumbing line. Treat it as a coordination clash and bring measured offset options for approval.

Open in Field Rescue Open category

Field verification checklist

Measure pipe size, elevation, slope, and duct centerline.
Check whether the pipe can move or is fixed by slope/structure.
Confirm insulation and service clearance.
Lay out possible 45° offset path without choking the duct.
Document the clash before modifying the run.

Ask foreman

The storm drain crosses our duct path at [location]. I measured the pipe, slope, and duct elevation. The clean options look like a 45 offset or revised route. Which direction do you want?

Text to foreman

Route options

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

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

C Bring 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 notch or flatten the duct to sneak around a storm drain pipe.

Why this matters

Bad clash fixes can restrict airflow, create condensation contact, and cause rework between trades.

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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