A vertical duct riser drifts out of plumb in a shaft

Do not force a heavy riser sideways to hit the next opening. Stabilize what is installed, verify shaft openings, and use an approved offset, transition, or support correction.

Stop if

• The riser is drifting out of plumb by about [amount] at [floor/location]. I checked openings and supports. Do you want to re-set support, add a riser support, or use an approved offset/transition to line up below?

Watch out

• Do not jam a heavy riser sideways or let the next section pull it into alignment by force.

Check

• Drop a plumb/laser reference and measure drift by floor/opening.
• Check shaft opening sizes, embeds, firestopping clearance, and access.
• Verify riser supports are carrying weight at the correct floors.
• Check whether the riser is binding against concrete, sleeve, or another trade.
• Ask before cutting, forcing, or changing riser geometry.

Steps

• Drop a plumb/laser reference and measure drift by floor/opening.
• Check shaft opening sizes, embeds, firestopping clearance, and access.
• Verify riser supports are carrying weight at the correct floors.
• Check whether the riser is binding against concrete, sleeve, or another trade.
• Ask before cutting, forcing, or changing riser geometry.

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