The Spiral Duct Manufacturers Association was formed to promote the use of round duct, spiral duct (spiral pipe) and flat oval duct through education and research informing the public of its advantages.

Garner, North Carolina-based Hamlin Sheet Metal was founded in 1954 by William F. “Fred” Hamlin to manufacture commercial air-handling ductwork.  Hamlin Sheet Metal became the first division of the Hamlin Cos., which now includes Hamlin Roofing, Hamlin Fabricated Metals and Ultratech Industries.

Many contractors have a comfort zone when it comes to the type of ductwork they prefer to use.

Let me start out by saying that before this summer, acronyms like HVAC or ASHRAE were simply groupings of familiar letters that stood for unfamiliar terms. The same goes for industry words like flat-oval duct, spiral duct — and well, a lot of variations that include the word “duct.”