What Kind of Sheet Metal is Used in HVAC Duct Fabrication?

Published Thursday, November 3, 2022

Veriform blog image what sheet metal for HVAC Ductwork. Rolled HVAC duct sheet metal.Ductwork fabrication is the process of fabricating customized parts for a building’s HVAC system. Due to their individual designs, homes and commercial buildings all have their own unique heating, cooling, and ventilation needs, which are accommodated by ductwork made from certain types of specialty metal. This blog examines how these ducts are made, what kind of sheet metal is used, and how VeriForm Inc. can produce the results you need.

How are Sheet Metal Ducts Made?

Duct fabrication sheet metal can be fabricated into a variety of shapes, including but not limited to: 

  • Straight oval pipes
  • Straight round pipes
  • X, Y and Z connector pieces
  • 90-degree elbows
  • Half sheet rectangular pipes

Fabrication of sheet metal ductwork involves cutting and forming. With cutting, shears and high-definition plasma equipment are used, while in forming, brakes and presses apply force to shape the material. With this equipment, precise cuts and bends can be created to create specific shapes and position ductwork around obstacles.

One of the most common solutions is rectangular metal ducts, which are formed by combining two bent pieces of sheeting. First, the flat pieces of metal need to be cut to the desired size using a plasma cutter or cutting machine. The sharp edges are then folded inward by another machine. The sheet is then shaped into an L or tube. Rectangular ducting is usually made to standard sizes, but custom sizes can also be created.

Another common option, round metal ductwork, is made using a different process. To begin the process, sheet metal is placed into a coiling machine. To make the pipe airtight, the machine fuses the edges together. Next, the pipe is cut to the desired length.

What Sheet Metals are Used for Ductwork?

Aluminum and galvanized mild steel are the two most common types of HVAC sheet metal.

Galvanized Mild Steel

Galvanized mild steel is highly pliable and can be formed into nearly any shape. This makes it an especially useful HVAC sheet metal for systems with unusual designs or installation requirements. A zinc coating protects the material from deterioration due to corrosion and rust. This ensures the longest possible lifespan in a ductwork system.

Suitable for industrial, commercial, and residential applications, galvanized mild steel can be easily cut, formed, and fabricated. Once fabrication is complete, the ductwork is wrapped in an insulating material to enhance performance and provide sufficient protection against air loss, thereby reducing energy costs. In addition to creating better airflow, galvanized steel sheet metal duct fabrication prevents mold and fungus growth.


The versatility of aluminum makes an ideal duct fabrication sheet metal, since it can be formed into sheets easily. Compared to traditional steel, aluminum is lightweight, making installation much easier, and extremely corrosion-resistant, which is why it is often used in outdoor applications. A typical aluminum sheet comes with pre-insulated panels, and sections are attached at the seams using aluminum tape and glue.

VeriForm Inc.: Sheet Metal Fabricators for HVAC Systems

At VeriForm Inc., we have a full-range metal fabrication service that can customize your sheet metal ductwork to fit your unique application. Our expertise in shaping, rolling, and cutting duct fabrication sheet metal allows us to deliver high-quality products with short lead times. 

In addition to these capabilities and custom ductwork fabrication, VeriForm Inc. also offers bulk duct fabrication, which allows us to supply large quantities of sheet metal ductwork right when you need it and at highly competitive prices. To learn more, please visit our website, call 519-653-6000 or contact us online.