DUCT FABRICATION BY INDUSTRY
The word duct covers a lot of ground. A commercial HVAC supply run and a plant dust collection system are both duct, but they are specified, built, and inspected to completely different standards. JMC fabricates across that range from one shop in Pascagoula, MS.
Here is how duct requirements change across the industries we serve, and what that means for the way we build it.
Published July 2, 2026 · JMC Fabrication
Each industry drives a different construction approach:
- Commercial construction: SMACNA-compliant rectangular, round, and oval HVAC duct in galvanized steel for offices, retail, institutional, and warehouse mechanical systems. High volume, coordinated to the mechanical package.
- Marine and shipyard: Corrosion-resistant duct for the saltwater environment, often stainless, built to survive humidity, washdown, and confined shipboard spaces.
- Oil and gas and industrial: Welded, heavy-gauge duct for dust collection, fume and process exhaust, and high-static or high-temperature service at refineries, chemical plants, and manufacturing facilities.
- Institutional and manufacturing: Ventilation and make-up air duct tied into plant airflow balancing, sized and reinforced for large-volume, long-run systems.
The two ends of the range differ on nearly every construction choice:
| Attribute | Commercial HVAC duct | Industrial / process duct |
|---|---|---|
| Governing standard | SMACNA | Process spec, NFPA where dust applies |
| Typical material | Galvanized steel | Heavy-gauge carbon or stainless steel |
| Seams | Slip-and-drive, flanged | Welded, leak-tight |
| Pressure class | Low to medium static | High static, positive or negative |
| Primary driver | Air comfort and efficiency | Material transport, heat, corrosion, safety |
A shop that only builds light commercial HVAC duct is not set up to weld heavy industrial duct, and a shop that only does structural work is not tooled for SMACNA sheet metal. JMC's background is heavy industrial fabrication, and we run commercial duct through the same facility, so we can match the build to the industry rather than force one approach onto every job.
Whatever the application, the process is the same: send us the drawings or the spec, and our engineering team takes it to production in-house.
Does JMC fabricate both commercial HVAC duct and industrial duct?
Yes. JMC builds SMACNA-compliant commercial HVAC duct in galvanized and stainless steel, and welded heavy-gauge industrial duct for dust collection, fume exhaust, and process ventilation, all from our Pascagoula shop.
Can JMC build duct for marine and shipyard work?
Yes. We fabricate corrosion-resistant and stainless duct suited to the saltwater, humidity, and washdown conditions of marine and shipyard environments.
How does industrial duct differ from commercial HVAC duct?
Industrial and process duct typically runs at higher static pressure, uses heavier gauge and welded seams, and is built from material chosen for the process, while commercial HVAC duct follows SMACNA and is usually galvanized with slip-and-drive or flanged seams.