TinnerFlow
Spiral & Round Duct · Straight Runs & Assembly

Spiral tee fitting

Main with branch

ConnectionSlip-fit/gasketed tee
SupportIndependent support at tee plus branch support

Before you start

  • Confirm the tee orientation and the branch angle against the drawing and against the airflow.
  • A tee installed backward is a rework.
  • Confirm the branch clears structure before the tee goes up, because once the main is connected on both sides you are not rotating it.
  • Stage the needed tools and materials before lifting the section: Tee fitting, independent support for the tee, branch support, sealant or gaskets, fasteners, screw gun, level, protractor or angle finder..

Tools and materials

Tee fitting, independent support for the tee, branch support, sealant or gaskets, fasteners, screw gun, level, protractor or angle finder.

Lay it out

  1. Confirm tee orientation and branch clocking against the drawing. Mark the branch position on the fitting.
  2. Connect the MAIN run first, both sides. The main is the reference.

Set and support it

  1. Install supports on the main BOTH SIDES of the tee before the tee goes up.
  2. Lift the tee independently. It gets its own support; it does not hang on the main joints.
  3. Support the branch.
  4. Use the approved support method for this condition: Independent support at tee plus branch support.

Make the connection

  1. 1

    Square the branch. Check the clocking against your mark.

  2. 2

    Connect the branch.

  3. 3

    Confirm the tee has not rolled. Once the branch is loaded it wants to rotate.

Check the install

  • Tee centered on the main run.
  • Branch clocked correctly, checked against the drawing.
  • No load transferred into the branch joint; the branch has its own support.
  • Tee has not rolled. Check the branch angle again after everything is loaded.

Common mistakes

  • Connecting the branch first. Now the main has to come to the branch and something gets forced.
  • Tee rolls under branch load because it was not independently supported.
  • Branch clocking off by a few degrees, and every fitting downstream inherits it.
  • Discovering the branch conflicts with structure after the main is sealed on both sides.

Stop and ask

Stop if branch conflicts with structure or tee orientation cannot match airflow plan