The Thermaduct Advantage


Thermaduct offers industry solutions to outdoor ductwork that exceed the ASHRAE and ICC Energy Codes present today and those 10 years from now. Our outdoor ductwork is available in the following insulation values.

  • R-8.1 (1x 1 3/16" Panel)
  • R-12 (1 x 1 3/4" Panel)
  • R-16.2 (2 x 1 3/16" Panel)
  • R-20 (1 x 1 3/4" Panel, 1 x 1 3/16" Panel)
  • R-24 (2 x 1 3/4 Panel)

Product Features

  • UL 181 Listed KoolDuct Liner
  • Passes the UL181 Mold Growth Test
  • Closed Cell Insulation
  • Highest R-Value Selections
  • Proven Low Air Leakage
  • 10 Year Limited Warranty*
  • UV Stable, 1,000 Micron Vinyl Cladding
  • Optional Interior Duct Options
  • Built in the USA
  • Union Made

No Tapes or Adhesives

Thermaduct is unique in the pre-insulated duct systems market in that it uses no tapes or adhesives when assembling pieces. Thermaduct’s vinyl cladding is heat or chemically welded together for an airtight seam that can't be matched with tapes or adhesives. Joints are connected with a gasketed 4 bolt flanging system and covered with Thermaduct's joint covers for extra protection from the elements.

1000 Micron Vinyl Cladding

Cladding for ductwork in outdoor environments is necessary for the long term durability in any installation. As the barrier to rain, wind, snow and hail it is vitally important for maintaining the R-value of pre-insulated ductwork. Thermaduct uses a 1000 micron titanium infused vinyl cladding to provide the toughest outdoor ductwork on the market. No tearing, denting or peeling means you keep the outdoor out.

Closed Cell Phenolic Foam

Thermaduct uses high quality closed cell phenolic duct to achieve some of the highest R-values available in the industry. Closed cell phenolic foam does not allow water to pass through, as can be the case with open cell phenolic foams. Pairing a strong, water resistant interior insulation with Thermaduct's exterior strength provides an unmatched product in outdoor environments.



Thermaduct is comprised of a Kingspan KoolDuct fortified cladded duct system in accordance with requirements of factory-made air ducts. Thermaduct OD is specifically designed for use in outdoor applications where adverse weather conditions will occur. Thermaduct incorporates the following standards:

UL 723, UL 181, 90A, 90B Interior;

ASTM D-638, ASTM D790, ASTM D-256, ASTM D-4226, ASTM D-4216, ASTM D-792, ASTM D-2240, ASTM D-696, ASTM D-648, UL-94 Exterior Cladding

Frictional Properties:

Thermaduct is a factory assembled air distribution system that employs a smooth aluminum surface that has frictional characteristics, much like that of galvanized sheet metal. As a result, the frictional pressure drop data for galvanized sheet metal ductwork can be applied when designing and specifying Thermaduct air distribution systems.

Operating Recommendation:

It is recommended that the application of Thermaduct supplied be utilized for operation as a supply, return, fresh air and exhaust air ductwork applications for heating, ventilation, and air conditioning applications.

Air Velocity (Maximum) 5000 fpm / 25.4 m/s
Design Pressure (Maximum) Positive and Negative 6 / 1500 Pa
Temperature Internal; Continuous -15°F to +185°F
Size Limitations None

Thermaduct can be designed to withstand up to a continuous maximum static pressure of 6 inches water guage / 1500 pa and is designed to have less than a SMACNA Air-Leakage Class 1 duct with the Thermaduct connection system.

By combining two layers of an autohesively bonded aluminum foil vapor barrier to the inner and outer closed cell Kooltherm insulation core, all protected with 1000 micron UV stable vinyl clad with welded or cohesively bonded seams, you simply can’t find a more air or water-tight outdoor duct system anywhere.

Additional Information

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