insulating exposed ductwork

Indoor Phenolic Installations

Whether you are installing Kingspan KoolDuct or our InspiralR and Floval Systems, these systems all offer a clean look with a paintable exterior that can easily blend into ceilings. These systems also offer many benefits of phenolic systems, including higher R-values, lower air leakage and upwards of a 70% reduction in weight.

Using professional grade water based, acrylic paints that can adhere to an aluminum surface have produced exceptional results and give this R-6 ductwork as clean of a look as any other exposed duct system. Once installed, you won't even know the difference until you look at your utility cost!

Pre-Insulated Double Wall Ductwork

Color Matching Your Exposed Phenolic Ductwork - Can Pre-Insulated Ductwork Match My Application’s Aesthetics?

Often times indoor applications have ductwork installed in clear view for building occupants. In some instances this is a design choice, looking to include ductwork into the architectural vision of the building, and others because of a necessity due to space restrictions. While traditional metal options are often associated with an industrial style look, once insulation is required options begin to change. Providing thermal resistance to your ductwork can be done in a variety of ways, each with their own pros and cons.

Phenolic duct systems are an excellent option for any interior installation that requires insulated ductwork to be manufactured. These SMACNA compliant systems are able to provide a minimum R-6 installed value free of loose interior fibers, reduced air leakage, substantially reduced weight and a clean, smooth surface that can be painted in a variety of color options. Always discuss paint options with your engineer before putting into practice.

Insulated duct Options for Exposed Applications

InspiralR Non Metal Ductwork

Option #1 - Pre-Insulated Phenolic Duct

Lightweight pre-insulated duct system with a paintable, smooth aluminum surface. Manufactured systems, such as Kingspan KoolDuct, InspiralR and Floval, are UL 181 listed and have excellent fire and smoke performance for indoor use.


Option #2 - External Duct Wrap

Open cell, fibrous liners installed over duct systems can provide adequate insulation value but require an additional layer of protection. The finished product often times leaves the duct system with a lumpy exterior look.

Lined Duct for Indoor Application

Option #3 - Internal Duct Liner or Double Wall Duct

Using open cell fibrous liners inside the duct can keep the industrial look, but create an environment for mold and bacteria growth if moisture is introduced. A "double wall" internal layer of metal is sometimes used to prevent this, but comes with added cost and weight.

Exposed Phenolic Duct Systems

Round Phenolic Pre-Insulated Ductwork

Additional Benefits of Phenolic Systems Over Traditional Insulated Ductwork

Phenolic ductwork can provide excellent results for exposed applications such as:

  • Lower air leakage prevents dust streaks on lighter colored ductwork
  • Space savings, as ductwork does not need the added space of insulation
  • Higher R-values prevents condensation and sweating of ductwork
  • Surfaces are oil free and do not require a special paint grip treatment

Making educated choices for your insulation can save you headaches down the road. If you find yourself wanting to increase the efficiency of your duct systems, both indoor and out, talk to your Local Thermaduct Expert or Contact Us to help you develop a plan for your building.

Insulated Ductwork for Architectural Applications

Looking for Something for the outdoor Duct Applications?

For outdoor or architectural applications, we offer a cladded version of our InspiralR system designed with Architects in mind! With multiple color options and finishes, this system does not use adhesives and meets the 25/50 flame and smoke spread requirements and is NFPA 90A complaint for use indoors or out.

For more information, visit our dedicated page for this custom colorful system!

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