Plenum branch collar

Before you start

• Confirm plenum construction, branch collar size, location, airflow direction, damper requirement, and manufacturer or equipment restrictions.
• Check the plenum for internal insulation, reinforcement, access panels, coils, filters, sensors, and service clearances.
• Verify the collar location will not damage internal components or block access.
• Support the cookie before the final cut.

Lay it out

1. Mark the collar opening from the approved branch centerline.
2. Check both the outside and inside of the plenum before cutting.
3. Keep the collar clear of reinforcement, service panels, and internal components.

Set and support it

1. Support the plenum or panel if the opening could distort it.
2. Clamp and square the collar before fastening.
3. Install the first branch support so the plenum does not carry branch weight.

Make the connection

1. 1

   Verify the inside of the plenum is clear.

2. 2

   Cut the opening while holding the cookie.

3. 3

   Deburr and clean the edge.

4. 4

   Repair or protect internal insulation as required.

5. 5

   Set the collar square and clamp it flush.

6. 6

   Install approved fasteners evenly.

7. 7

   Seal the collar with the material compatible with the plenum construction.

8. 8

   Connect and independently support the branch.