Spiral HVAC DuctArmacell is the market leader in elastomeric foam insulation for ducts and hot- and cold-water piping in HVAC systems.

HVAC systems should be designed to make the most of every kW that goes into the heating or cooling of water or air for the purposes of indoor comfort.  Insulating HVAC piping and ducts is not only smart, it’s required by most codes.

Armacell makes a range of products that make it easy to build an environment that will have thermal efficiency and acoustic benefits for years to come. Whether it’s a new construction project or a retrofit job, there is an Armacell insulation that meets the needs of your heating, cooling, and/or ventilation design.

HVAC Roof Install

  • AP ArmaFlex® is the ideal choice for duct wrap or duct liner. Available in sheets and rolls, in regular or self-adhering material, this closed-cell foam insulation requires no additional vapor barrier and meets the stringent flame and smoke testing required for use in air plenums. AP ArmaFlex can be used in new construction or in insulation retrofits.

  • AP CoilFlex® foam insulation is especially well suited as duct liner on newly constructed duct systems. This super-flexible and conformable insulation can be applied to sheet metal duct using automatic coiling equipment, making it extremely easy to apply. Non-particulating AP CoilFlex provides the sound attenuation required in mechanical systems without the fibers or the need for additional vapor retarder or dual wall duct. Foam duct liners are also easier to clean and maintain and may require fewer call-back and replacements over the life of the system.

  • AP ArmaFlex Black Lap Seal and AP ArmaFlex insulation of hot- and cold-water piping systems in HVAC systems, AP ArmaFlex can be selected in a variety thicknesses, pre-slit or not, and with or without self-adhesive strips. The closed-cell foam structure of AP ArmaFlex makes it especially effective at protecting pipes from condensation and moisture, which can compromise the structure and thermal properties of fibrous pipe insulation.

All Armacell AP products contain Microban antimicrobial technology to ensure resistance to the growth of mold. And AP ArmaFlex and AP Coilflex are also GREENGUARD Gold certified, meaning that they are certified to GREENGUARD standards for low chemical emissions for indoor applications. For more information, visit UL GREENGUARD here.


  • 25/50 flame and smoke rated up to 2”

  • Meets the energy code requirements of ASHRAE 90.1, ASHRAE 90.2, International Energy Conservation Code (IECC) and other building codes

  • Made without the use of CFCs, HFCs or HCFCs

  • Formaldehyde free, low VOCs, fiber free, dust free

  • Made with Microban® antimicrobial product protection for added defense against mold on the insulation

Variable Refrigerant Technology (VRF/VRV)

VRV and VRF systems have been used extensively in markets outside of the United States. In recent years, these systems have become more popular in the US as building operators and owners realize the energy efficiency of these systems and the flexibility they offer for climate control in multi-zone buildings.

System Operating Conditions

Some VRV/VRF manufacturers cite a 250°F requirement for insulation for abnormal temporary situations when there is a problem with the system and repair is required. In this temporary situation, refrigerant may become superheated and reach temperatures up to 250°F before the unit shuts down automatically.  The time that the refrigerant temperature would be above the upper use temperature of AP ArmaFlex would be minimal and likely less than 10 minutes. 

AP ArmaFlex has been tested to ASTM C411, Standard Test Method for Hot-Surface Performance of High-Temperature Thermal Insulation, where it is subjected to 250°F for 96 hours.  During this test, AP ArmaFlex shows no signs of sagging, surface cracking, warping, or de-lamination and the insulation remains flexible and easy to handle.  In addition, there is no smoking, flaming, glowing or smoldering on the inner diameter of the insulation.  Since ASTM C411 proves that AP Armaflex can handle 250°F for 96 hours, it can handle the short amount of time VRF or VRV refrigerant may be at 250°F during faulty, abnormal operation.

Read more about VRF/VRV Systems here.

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