Join light-duty rectangular riser duct

Before you start

• Confirm the duct size, end construction, pressure class, seal class, and joint shown on the approved shop drawing.
• Inspect both duct ends for crushed corners, torn locks, bowed panels, loose reinforcement, or shop damage before lifting them into place.
• Make sure the supports are already installed or the sections are otherwise held so the joint is not carrying the weight of the run.
• Stage the correct S-cleats, drive cleats, sealant, hand tools, clamps, and access equipment before starting the joint.
• Confirm the riser support, floor frame, guides, and load path are approved for the duct section being installed.

Lay it out

1. Use a continuous plumb reference through the shaft or floor opening.
2. Verify the opening, sleeve, firestop allowance, and riser dimensions before lifting.
3. Identify where the riser dead load transfers to structure and where lateral guides are required.

Set and support it

1. Set and secure the lower riser section on its designed support.
2. Rig the upper section from approved lifting points and keep it controlled against rotation.
3. Lower or raise the section until the faces align without loading the transverse joint.

Make the connection

1. 1

   Install the horizontal S-cleats while both sections are supported.

2. 2

   Align the four corners and confirm the riser remains plumb.

3. 3

   Start the vertical drives and seat them fully while the rigging remains attached.

4. 4

   Secure the drive ends and complete the required seal.

5. 5

   Transfer the section weight to the riser support as designed.

6. 6

   Install lateral guides or restraints before releasing rigging.