Atmosphere Air Duct Board

Atmosphere Air Duct Board

Knauf Insulation Atmosphere™ Air Duct Board with ECOSE® Technology is a rigid glass mineral wool board faced on one side with a foil-scrim-kraft (FSK) vapor retarder and with a lightweight non-woven mat on the airstream surface. It is used to fabricate rectangular or Max10 air duct systems. Available in two stiffness ratings, EI-475 or EI-800. Both types are available with butt edge or factory molded male-female shiplap edges.ECOSE Technology.

ECOSE technology is a revolutionary binder chemistry that enhances the sustainability of our products. The “binder” is the bond that holds our glass mineral wool product together and gives the product its shape and brown color. ECOSE technology is a plant-based, sustainable chemistry that replaces the phenol/formaldehyde (PF) binder traditionally used in glass mineral wool products. Products using ECOSE technology are formaldehyde-free and have reduced global warming potential when compared to our products of the past.


Knauf Insulation Atmosphere™ Air Duct Board with ECOSE® Technology is designed for commercial and residential air handling installations for cooling, heating or dual-temperature service where good temperature control and noise absorption are required.

Thickness (mm) Length (m) Width (mm) Area per pack (m²) Slabs per pack
25 2440 1200 23.81 8
50 2440 1200 11.6 3



  • Carbon negative: Knauf Insulation’s products used for thermal insulating purposes recover the energy that it took to make them in just hours or a few days, depending on the application. Once installed, the product continues to save energy and reduce carbon generation as long as it is in place.
  • Glass mineral wool insulation with ECOSE® Technology contains three key ingredients:
    • Sand, one of the world’s most abundant resources
    • A minimum of 50% recycled glass content and UL Environment verification every 6 months
    • ECOSE® Technology which reduces binder embodied energy by up to 70%
    • It reduces its Global Warming Potential (GWP) by approximately 4%, a significant reduction in our carbon footprint


  • Fabrication in shop environment lowers field installation time
  • One trade required to fabricate and install system
  • Minimum capital investment for fabrication equipment
  • Portability allowing for assembly or fabrication at job site
  • ECOSE mat facing ensures a smooth airstream surface for a clean cut and durability
  • Lower installation cost than with duct wrap or duct liner with sheet metal
  • Dark internal duct appearance
  • Quiet, efficient air delivery
  • Reduces noise generated by air turbulence and mechanical equipment
  • Eliminates “booming” and “cracking” sounds caused by sheet metal duct contraction and expansion

Application and Specification Guidelines


  • Duct shall be fabricated and installed in strict accordance with NAIMA’s “Fibrous Glass Duct Construction Standard,” “Residential Standard,” or “2” Fabrication Manual” in accordance with the conditions of UL 181 listing. Duct systems shall have all transverse joints, longitudinal seams and duct wall penetrations sealed using 3” (76 mm) wide glass fabric and mastic, 2” (51 mm) minimum width heat sealable tape or 2” (51 mm) minimum width pressure sensitive tape with acrylic adhesive. Rubber-based adhesives are not approved.
  • Only UL 181-A listed and labeled products shall be used for closure systems. A listing of specific approved closure products is available from your local Knauf Insulation sales representative.
    PRESSURE SENSITIVE TAPES: Only those tapes listed under and imprinted with designation UL 181-A-P and registered with UL.
    HEAT SEALABLE TAPES: Only those tapes listed under and imprinted with the designation UL 181 A-H and registered with UL.
    MASTICS: Mastic systems listed and registered with UL and carrying the designation UL 181 A-M used in conjunction with a 3” (76 mm) wide glass fabric.



a. All longitudinal and circumferential joints must be stapled with outward flaring, ½” (13 mm) minimum length staples 2” (51 mm) on centers.
b. If necessary, follow the recommendations of the tape manufacturer for cleaning the surface to be taped.
c. Center tape over staple flap and rub tape firmly in place immediately after application, using a plastic “squeegee” or similar tool, until the scrim reinforcement of the duct board facing can be clearly seen through the tape.
d. A heat-sealing iron must be used to warm the surface of the board before applying the tape to assure a good bond when installed below 50°F (10°C).
e. Tape should not be applied to surface of duct board when temperature is below 32°F (0°C) due to the possibility of entrapping ice crystals which, upon melting, will cause tape to loosen. Heat duct board facing surface first to drive off moisture.


b. If necessary, follow the recommendations of the tape manufacturer for cleaning the surface to be taped.
c. Center tape over staple flap and seal down tape end with 500°F (260°C) iron. Do not use heat gun; both heat and pressure are required to effect a seal.
d. Press down entire length of tape with iron using a smearing action to get a good bond. Be sure edges are sealed.
e. Staples may be omitted when an automatic closure machine such as the Glassmaster Closemaster is used. In this case, iron temperature must be set at 650°F (343°C) minimum. Continuous production may require periodic pauses to allow sealing iron temperature to recover to the 650°F (343°C) minimum.
f. Allow joint to cool before stressing.


a. All longitudinal and circumferential joints must be stapled with outward flaring, ½" (13 mm) minimum length staples 2" (51 mm) on centers.
b. Brush approved mastic onto joint and embed 3" (76 mm) wide glass fabric in mastic.
c. Brush second coat of mastic over glass fabric until mesh is completely filled.
d. Follow mastic manufacturer’s instructions on curing the mastic prior to subjecting the joint to stress.


If the closure system used is not one of the approved systems described above and if application is not in accordance with stated procedures, Knauf Insulation assumes no liability for duct system performance. Use of a non-UL registered and listed closure voids the UL 181 Class 1 rating as well as Knauf Insulation’s product performance warranties.


Duct sections shall be additionally reinforced where necessary, according to NAIMA standards. Ductwork shall be supported a required on straight runs, at all turns and at transitions to maintain proper alignment. Hangers and supports shall be in strict accordance with NAIMA standards.

Maintained Duct Systems are Key

The best way to ensure that an HVAC system, whether bare metal or internally insulated, will continue to provide efficient, quiet air delivery, occupant comfort, and cost-effectiveness is by following a regular system operation and maintenance schedule. This, along with a high-efficiency filtration system, assures protection of both HVAC system components and building occupants. Maintenance procedures include inspection, detection and remediation of probable sources of airborne contaminants and moisture. Glass mineral wool insulation will not sustain mold growth. However, mold can grow on almost any material when it becomes wet and contaminated. Carefully inspect any insulation that has been exposed to water. If it shows any sign of mold, it must be discarded. If the material is wet but shows no evidence of mold, it should be dried rapidly and thoroughly. If it shows signs of facing degradation from wetting, it should be replaced. Air handling insulation used in the air stream must be discarded if exposed to water.


When used in accordance with NAIMA’s application instructions, the closure systems described herein meet UL 181 requirements, and the resulting system carries a Class 1 Air Duct rating. This data sheet is not intended to be a design or fabrication manual. For specific details and recommendations on fabrication, reinforcement, hanging and other details, refer to the latest edition of the NAIMA “Fibrous Glass Duct Construction Standard,” “Residential Standard,” “2” Fabrication Manual.” Application and installation procedure is at the discretion of and is the responsibility of the Design Engineer to meet specific job requirements.

The chemical and physical properties of Knauf Insulation Atmosphere™ Air Duct Board with ECOSE Technology represent typical average values determined in accordance with accepted test methods. The data is subject to normal manufacturing and testing variations. The data is supplied as a technical service and is subject to change without notice. References to numerical flame spread ratings are not intended to reflect hazards presented by these or any other materials under actual fire conditions.

Check with your Knauf Insulation sales representative to assure information is current.

Atmosphere Air Duct Board

  • October 2016