Duct Collar

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Duct Collar

What is Duct Collar?

A duct collar is an HVAC fitting used to connect ductwork to equipment, plenums, or building openings.

Description

A duct collar is a short, cylindrical or rectangular HVAC fitting that provides a transition point between ductwork and another component, such as an air handler, plenum, register box, or wall or ceiling opening. It creates a secure connection that allows airflow to move smoothly through the system.

In construction and HVAC installation, duct collars are commonly made from galvanized steel, aluminum, or other sheet metal. They are often equipped with tabs, flanges, or beads to help secure flexible or rigid ducts using clamps, screws, or sealants. Proper sizing is essential to ensure airtight connections and consistent airflow.

From a performance standpoint, duct collars play an important role in reducing air leakage and maintaining system efficiency. Sealing collars with approved mastic or tape helps prevent energy loss and improves overall HVAC performance. In both residential and commercial systems, correctly installed duct collars support code compliance and long-term system reliability.

FAQs

  • What is a duct collar used for?

    It connects ductwork to HVAC equipment, plenums, or air distribution openings.

  • What materials are duct collars made from?

    Most duct collars are made from galvanized steel or aluminum.

  • Are duct collars used with flexible ducts?

    Yes, duct collars are commonly used to attach flexible duct to equipment or plenums.

  • How are duct collars sealed?

    They are sealed using mastic, foil tape, clamps, or a combination of methods.

  • Are duct collars required by code?

    Codes typically require duct connections to be properly secured and sealed, which duct collars help achieve.

Fun Fact

A properly sealed duct collar can prevent enough air leakage to noticeably improve HVAC efficiency and comfort.

CSI Code

23 31 13

NAHB Code

3610