If you're building a commercial building from scratch, you're going to need commercial ductwork. (Check out this guide for more info.)
If you're not sure what's what when talking to contractors, the sheet metal experts at Kaempf & Harris have come up with this comprehensive list of common commercial ductwork parts:
Access Door: Used to allow access to an enclosed space behind a wall, floor, or ceiling
Elbow: Used to make necessary tight corners for maintaining the best airflow for maximum efficiency in HVAC ductwork
Ceiling Box: Used to attach a register in the ceiling to supply air in any room
China Cap: Used to mount on the top of a piece of sheet metal duct that extends through a commercial building’s roof to keep rain and snow out of the duct system
Damper Sleeve: Used to regulate the amount of air flowing through each branch of a commercial building’s heating and air conditioning ductwork
Duct Booster Fan: Also known as a booster fan, a device used to increase airflow to different rooms in the building that are farther away from heating and cooling systems
Duct Sealant: A way to seal ductwork in order to prevent leaks, holes, and poorly connected ducts
End Cap: Galvanized steel that’s used to terminate a commercial ductwork run
Flashing: A series of metal vent pipes that exhaust hot air from a natural gas heating unit or ventilation fan through the roof, usually sealed with mastic to prevent water leakage into a commercial building
Flex Duct: Also known as flex, a flexible plastic that can be molded over a wire coil to shape a tube for thermal insulation
Floor Box: Also known as a register box, a galvanized steel grille with moving parts that’s capable of being opened and closed with the airflow directed
Hanger Strap: Used with or without holes to hang HVAC manifold gauges during ductwork installation
Manifold Gauge: A three-chamber assembly that has three ports and two valves that are used to check the pressure, supply, and drain of an air conditioning unit
Pancake Taper: Round connectors used to butt joins together while transitioning in size
Plenum: An air distribution box that heats or cools the air and is directly attached to the supply outlet of the HVAC equipment and connected to the ductwork
Reducer: A ducting fitting used when a change from one size duct to another size is needed
Return Air Diffuser: Used to introduce conditioned air into a space to achieve even distribution and mixing with minimum noise
Saddle Tap: Used to branch a round duct run off of another round sheet metal duct run at a 45-degree angle for improved airflow and efficiency
Stackhead Boot: Also known as a stack boot, used to transition a round pipe or flexible insulated duct to oval pipe or a sidewall grille or register
Start Collar: Used to transition from a flat surface that’s made from metal, ductboard, or insulated liner to a round pipe or insulated flexible duct
Straight Boot: Used to transition from a round branch off of a main supply duct to a floor, wall or ceiling register
Supply Air Diffuser: An air terminal device that distributes conditioned air in various directions through the use of its deflecting vanes and is designed to promote the mixing of conditioned air with existing air
Vent Cap: A fitting that provides protection for the open end of a ductwork vent stack
Wye: A short pipe with a branch joining it at an acute angle
For a labeled diagram of basic commercial ductwork, download Kaempf & Harris' Commercial Ductwork Anatomy infographic by clicking on the button below: