Apprentice answer

What is the symbol for a drop (duct going down) versus a rise (duct going up)

2nd YearPrint Reading, RFIs & Trade CoordinationCheck first

Duct Drop: Typically noted on the floor plan with a square box containing a diagonal 'X' pattern or a solid shaded black pattern accompanied by the abbreviation DN (Down). * Duct Rise: Typically noted with an open square box containing a central target dot or a single clean slash line accompanied by the abbreviation UP.

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Plain-English answer

Field checklist

Duct Drop: Typically noted on the floor plan with a square box containing a diagonal 'X' pattern or a solid shaded black pattern accompanied by the abbreviation DN (Down). * Duct Rise:...

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Hey boss, I’m checking blueprint reading: What is the symbol for a drop (duct going down) versus a rise (duct going up)? I found the likely issue and want to verify the next step before I lock it in. Do you want me to adjust it now or check the drawing/detail first?

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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.

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