How do you install ductwork?

To install ductwork, ensure that the grills and registers are connected to the HVAC system correctly before testing. The system should have enough airflow through each grill. Check for leaks by walking or crawling along the duct lengths.

1. Attach duct boards and drives

   Attach duct boards together with a system of drives and S-cleats following the transitions necessary for trunk installation. Use the S-cleats to connect the tops and bottoms of the ducts. Each piece of ductwork fits into a separate slot. Attach the drives to the sides, and bend them to lock them into fixed positions. Install the end cap to the end of the trunk.

2. Make holes into the sides of the trunk for branch ducts

   Cut either rectangular or circular cross-section holes into the sides of the trunk. Rectangular holes are necessary if the branch duct splits into two branches. However, if you choose flexible ductwork as branch ducts, use round holes. Size the holes according to the branch. Join the branch ducts and the trunk using a piece of metal called a joining collar. Follow the same procedure to install the flexible ducts. In most cases, technicians use flexible ducts as termination ducts because it is easy to install them, and they do not require an exact fitting.

3. Install the registers

   Installation of registers takes place when the office or home is almost complete. At minimum, the drywall needs to be completely textured and painted. It is also important to cover the floor before installing registers.