Hennemuth Metal Fabricators (HMF) is a family owned, full-service duct manufacturer specializing in spiral and rectangular ductwork for commercial and residential HVAC contractors in Pittsburgh and the surrounding tri-state area. Located in Oakdale, Pennsylvania, HMF has a 60,000 square-foot semi-automated facility where they make their own spiral duct and fittings.

Although HMF has been in business since 1954, they are relatively new to making spiral duct. HMF purchased their spiral equipment in 2018 from Spiral-Helix. According to Vince Weber, HMF’s spiral shop foreman, “There was your typical learning curve, but we worked through it.”


By November 2018, HMF had refined their process, began to make spiral on a consistent basis, and had started to produce their own fittings. Weber notes that since they have been making their own fittings, customer satisfaction has also increased. “Our customers love our spiral because it fits perfectly. And it fits perfectly because we make all of our own fittings. When we make spiral we check both the pipe and the fittings and we can adjust our fittings to make sure everything goes together well. So if you buy both the pipe and fittings together, they are guaranteed to fit.”

One of HMF’s recently completed spiral projects was for ClimaTech, the mechanical contractor working on Amazon’s $30-million-dollar, 1.2 million square foot fulfillment center project in Findley Township. This job included 36” single wall, 22-gauge galvanneal spiral with 2” Owens Corning’s QuietR® Spiral Duct Liner.

According to Brett Barker, HMF’s shop foreman, in addition to using HMF’s fittings, “We recommended that ClimaTech use HFC Enterprises’ DuraFlange and DC ring set on this job because we find it is an efficient, rigid, and lightweight connector that really saves the installers time on field labor. According to the manufacturer, these products have been tested to +/-10W.G. with virtually no leakage, so we feel confident in recommending the system to our clients.”

Rob Airgood, field foreman at ClimaTech, commented on just how effective this entire system was for them, “This was the first time we’ve used your products. I’ve been doing this for 24 years, and I would say that your spiral product was second to none … It goes together a lot easier than anything else I’ve ever used and it’s a real time saver out in the field too. It’s solid. Just the way it was built. Real quality work.”

Now two years into their spiral production, HMF has made everything from 4” to 40” lined and unlined spiral. They have found that although sales were sluggish at first, sales have more than quadrupled over the past two years providing “nearly 30 percent of our annual sales,” according to accounts manager, Hilary Barker.

Overall, HMF has found the expansion to spiral production to be successful and they are looking forward to expanding the line with antimicrobial-coated spiral products.

This article originally appeared in the January 2021 issue of SNIPS magazine.