Can a structural column pass through a low-pressure return duct?

A column in a return duct path is not an apprentice-level field modification. Stop, measure the conflict, protect the opening, and get an approved detail before building around structural concrete or steel.

['A return duct running into a fixed structural column is a coordination/design issue. Sometimes the recovery may involve rerouting, splitting the duct, enlarging the duct around the obstruction, or building an approved internal shroud, but that decision belongs to the foreman/detailer/engineer.', 'The apprentice value is to gather clean field information: exact location, duct size, column size, available space on each side, airflow direction, access, and what is downstream. Do not cut, notch, flatten, or freestyle a duct-around-column solution.']

Stop if

• Use this as training guidance. The foreman, approved drawings, project specs, manufacturer installation instructions, employer safety policy, and AHJ/code requirements always control the final answer.

Check

• Changing duct area or building around structure can affect airflow, pressure, access, coordination, and responsibility for the final design.

Steps

• Verify the column location against structural and coordination drawings.
• Measure available clearance left/right/top/bottom and the duct path before and after the obstruction.
• Check whether the duct is return, supply, exhaust, rated, lined, insulated, or pressure-class sensitive.
• Look for access, future cleaning/service, and whether another trade can move.
• Send photos, measurements, and gridline/location for a detail/RFI decision.

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