ANAHEIM, Calif. - Ductwork has some new responsibilities. If the 2004 International Air-Conditioning, Heating, Refrigerating Exposition (AHR Expo) is any indication, ductwork and duct accessories no longer just move the air around an environment. They now help to keep the environment clean, as well as minimize and eliminate sound from HVAC systems.

Ductwork is also coming in a variety of sizes and shapes in order to accommodate every application a contractor could find in the field.

The EnviroAire™ XG™ fiberglass duct board, manufactured by Johns Manville, is a naturally white, formaldehyde-free board air duct product, developed to enhance indoor air quality and absorb noise.

Protecting Ducts

Indoor air quality (IAQ) continues to have an impact on the industry, especially from a marketing standpoint. Now duct products are getting into the IAQ game. For example,JP Lamborn Co.( introduced what it says is its latest "flex duct with a new twist."

The company's AMBlue flexible air duct is constructed with an inner core of co-extruded blue nylon film. The film, according to the company, has antimicrobial properties integrated into the co-extrusion process. The antimicrobial film in the duct is said to resist mold fungus growth.

According to JP Lamborn, the AMBlue flexible duct is more beneficial than duct sprays and coatings because the product covers the entire surface area of the duct and will not flake off over time, stated the company.

Atco Rubber Products ( introduced a flex duct during the expo that is intended to work better with ultraviolet (UV) bio-treatment lamps and UV air purifiers in air-handling systems.

According to Atco, the use of UV bio-treatment lamps continues to rise. These lamps can have a deteriorating effect on the inner core of some nonmetallic flexible duct, says the company. To solve this problem, Atco developed the Ultra-Flex flexible duct kit. The company said that the new flex duct should be used to replace existing flexible ductwork that is directly exposed to damaging ultraviolet radiation from UV bio-treatment lamps. The Ultra-Flex is said to stand up to the radiation from such UV lights.

Spiracoustic Plus™ insulation from Johns Manville.
Titus( introduced EnviroLoc, which is an IAQ liner available at no additional cost over standard fiberglass liner. The new liner is an environmentally friendly, thermally bonded, high-density, acoustic/thermal insulation designed for HVAC systems. EnviroLoc is treated with a boron-based, EPA-approved fire retardant, which limits fungus and mold growth, said the company.

The liner is manufactured to accept and release any moisture received in a timely manner. Constructed of natural cotton fibers containing no harmful irritants, the liner is safe to handle and will not cause itchy or irritated skin, stated the manufacturer.

Ductsox ( was recently recognized by for having a "GreenSpec" product. The product, which was on display during the show, is the Ductsox fabric duct. Fabric duct is used in place of metal ducts, which can create challenges in retrofit applications, stated the company.

According to Ductsox, fabric duct is environmentally friendly; not only does it eliminate the need for metal ducts, it can improve air quality with more even air disbursement, conserve natural resources, reduce solid wastes in shipping materials, and decrease greenhouse gas emissions by limiting the spread of air pollutants.

During the expo, Ductsox also introduced its Adjustable Flow Deviceâ„¢ (AFD), an in-duct system for regulating fabric duct airflow and static pressure. The AFD is a polyester mesh cone with a factory-set or field-adjustable hemmed drawstring aperture for air balancing all models of Ductsox fabric air dispersion models.

Pictured is the Adjustable Flow Device (AFD) by Ductsox. The product is designed to regulate fabric duct airflow and static pressure.

Space Challenges

The Ductsox fabric duct was just one duct product at the show that was developed with space in mind.Energy Saving Products Ltd.( is the maker of the Hi-Velocity Soft-Aire® Home Comforte System. The system is designed to improve IAQ and save on space. The Soft-Aire Systems are prewired for heating, cooling, and ventilation so no additional controls are needed.

Also, the Space Saver fancoils can be placed in a horizontal, high-boy, or counterflow position. The units then are used in conjunction with the company's compact duct and flexible 2-inch duct. According to the company, the 2-inch duct means less custom sheet metal and less waste. It also saves on construction dollars.

On the commercial side, Casco ( introduced its Big Flex Duct. When larger-sized duct is needed, Casco can provide flex duct in sizes from 22 to 36 inches.

According to the company, the product is lower in cost per foot than spiral duct and lighter. This makes it easer to ship and saves on freight cost. Casco said that the Big Flex Duct is easier to install than spiral duct, and comes boxed with hanger straps. The product has built-in acoustical properties that metal duct does not have.

The Linacoustic® XG™ duct liner introduced by Johns Manville.

Keep Out The Noise

Several manufacturers previewed new duct insulation products developed to reduce noise levels.Johns Manville( introduced Linacoustic® XG™ and EnviroAire™ XG, both designed to reduce sound levels inside ductwork. They were both developed with IAQ in mind. The EnviroAire XG is a naturally white, formaldehyde-free fiberglass duct liner manufactured to enhance IAQ. The same is true for the Linacoustic XG. Both products are manufactured with a Reinforced Coating (RC) system, which Johns Manville said protects the airstream surface.

The Spiracoustic Plusâ„¢, available for over 10 years in large-diameter ducts, is now kerfed with very small diameter (VSD) groove configuration that makes it practical in metal ducts as small as 8 inches in diameter.

Also new from Johns Manville is the SuperDuct® RC, which combines the company's SuperDuct Air Duct Board with the benefits of the RC System.

CertainTeed (, which celebrates its 100th anniversary this year, displayed several new products. The company introduced its Isopureâ„¢ Filter Media, a fiberglass insulation used to produce pocket filters for the OEM market.

CertainTeed educated contractors on its MemBrainâ„¢ vapor retarder used in conjunction with building insulation to allow excess moisture to escape from wall cavities. In the duct market, CertainTeed announced the coming of its ToughGard 2 textile duct liner installation. The product rollout is tentatively scheduled for summer 2004, and is being developed to provide thermal and acoustical performance.

Keith Jordan of ATCO Rubber Products shows a section of the company’s flexible duct, which is designed to stand up to the radiation of UV lights. (Photo by Jim Johnson.)

Accessories And More

Metal-Fab Inc.( highlighted its new Model 2G grease duct. The factory-built grease duct was submitted to the same rigorous test standards as 4G, and 2G is classified as an alternate to one-hour fire-resistive shaft enclosure. Fabricated with 2 inches of insulation that is fully enclosed with a steel jacket, 2G is also UL listed.

Director of sales Bill Wesche said this grease duct system works especially well for stand-alone restaurants. "It's also extremely cost effective and re-quires only about one-quarter of the time to install versus other duct systems," he said.

Telaire ( introduced its SuperDuct duct detector. The detector is placed in a return-air duct and a supply-air duct. A controller is then used to read both detectors for a variety of functions. The detectors can monitor demand-controlled ventilation, infrared dewpoint, in-flue sensing, gas and particulate sensing, smoke detection, combustible vapor detection, CO2 monitoring, and leak detection.

Mamac System ( gave attendees a look at its newest duct temperature sensors. The sensors come in a variety of models that vary by installation type, sensor type, and probe length.

For more new product roundups from the AHR Expo in this online issue, see the features "Commercial Boilers Focus On Low NOx," "New Advances In Grilles, Registers, and Diffusers," "This Is Only A Test," "It's A Wide, Wide World Of Thermostats," "Motors, Pumps, And Drives Have Strong Presence," and "Chillers And Air Handlers Offer Many Options."

Publication date: 03/08/2004