It appears our June cover story (“The end of sheet metal?”) on a Massachusetts inventor’s alternative to sheet metal went over like a dented piece of ductwork.

I chose to profile David Carpinetti and his company, Black Duck Industries, because I am always interested in unusual people and products related to the sheet metal and HVAC industry. I thought the story of his attempt to use online crowdfunding to begin manufacturing his plastic sheet metal duct replacement demonstrated the creativity and persistence of people in this industry.

But that’s not the way some readers and advertisers took it. They felt I was calling sheet metal an outdated material and was turning SNIPS’ back on the material and machinery makers that have supported it for 84 years.

That’s not true. Sheet metal is — and I expect will be — the HVAC construction material of choice for many applications for years to come. But ductwork is not just made from sheet metal anymore, and it would not be accurately reporting on the industry if we acted as it was. When designing HVAC systems, engineers can now choose from flexible, fabric, fibrous glass and phenolic materials in addition to sheet metal. Most of the other materials have specialized applications that make them unlikely to replace the rectangular metal contractors most often make and install.

But the same sheet metal workers who install metal duct may one day be hired to hang fabric duct above an indoor swimming pool or phenolic ductwork in a high-efficiency green building. That’s why we write about them.

What do you think of Carpinetti’s idea or other potential alternatives to sheet metal? Go to our Facebook, LinkedIn or Google Plus pages and talk about it.