External Duct Insulation

At Johns Manville, we’re committed to the details that matter to you. We offer a range of fiber glass duct wrap solutions that provide traditional sheet metal ducts with improved thermal insulation. Our duct wrap is available in a variety of densities, thicknesses and with or without facings.

In addition, JM Microlite® EQ is now manufactured with a bio-based binder made primarily of rapidly renewable, plant-based materials, which satisfies the industry’s growing demand for agriculturally sourced products. Installing contractors prefer it for many reasons, including improved handling, easier cutting and less dust. Residential and commercial building occupants appreciate the consistent temperatures and improved comfort and energy efficiency that JM fiber glass duct wrap provides.

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Fiberglass equipment and duct insulation (service temp: 450°F)

Johns Manville 800 Series Spin-Glas® equipment and external duct insulation provides a broad range of solutions to meet your unique application needs. The breadth and depth of our product availability includes plain, FSK or AP faced board, where the facing acts as a vapor retarder. You can be assured you are getting the same superior performance from the facing as the insulation because we manufacture both to the highest quality standards. 800 Series Spin-Glas board is easily fabricated for an excellent finished appearance on duct and equipment systems. 

Density (pcf): 1.5 - 6.0
Service Temp (Nominal): 450° F
Thermal Conductivity (k): 0.22-0.24
Recycle Content: 18%

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Available Documents

Formaldehyde-free fiberglass blanket duct wrap with an FSK facing, manufactured with a binder made from renewable plant-based material. (Transitioning to Microlite FSK)

Microlite® EQ FSK Formaldehyde-free™ duct wrap offers superior thermal performance and condensation control in a lightweight, blanket-type insulation with an FSK facing. It is recommended for HVAC system exteriors or surfaces where design parameters prohibit the use of liner or board. Installing contractors prefer Microlite EQ’s bio-based binder for many reasons, including improved handling, easier cutting and less dust. Our manufacturing process ensures consistency during production, which results in reliable product quality. 

R Value: 4.2 (1.5")
Permeance Rating (Facing): 0.02
Recycle Content: 24%
Greenguard: Gold

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Available Documents

Formaldehyde-free fiberglass blanket duct wrap with a PSK facing, manufactured with a binder made from renewable plant-based material.

Microlite® EQ PSK is a Formaldehyde-free™, lightweight, blanket-type insulation with a PSK facing for superior thermal and condensation control. It is recommended for HVAC ducts or surfaces where design parameters prohibit the use of a board product. Installing contractors prefer Microlite EQ’s bio-based binder for many reasons including improved handling, easier cutting and less dust. Our manufacturing process ensures consistency during production, which results in consistent product quality

Permeance: 0.02
R-value: 4.2
Recycle Content: 24%
Greenguard: Gold

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Available Documents

Formaldehyde-free® fiberglass, blanket-type duct wrap with FSK facing. (Service temp: 250°F)

Microlite® FSK Formaldehyde-free™ duct wrap offers superior thermal performance and condensation control in a lightweight, blanket-type insulation with an FSK facing. It is recommended for HVAC system exteriors or surfaces where design parameters prohibit the use of liner or board. Installing contractors prefer Microlite's binder for many reasons, including improved handling, easier cutting and less dust. Our manufacturing process ensures consistency during production, which results in reliable product quality.

R Value: 4.2 (1.5")
Permeance Rating (Facing): 0.02
Recycle Content: 24%
Greenguard: Gold

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Available Documents

Formaldehyde-free® fiberglass, blanket-type duct wrap with PSK facing. (Service temp: 250°F)

Microlite® PSK Formaldehyde-free™ duct wrap offers superior thermal performance and condensation control in a lightweight, blanket-type insulation with an PSK facing. It is recommended for HVAC system exteriors or surfaces where design parameters prohibit the use of liner or board. Installing contractors prefer Microlite's binder for many reasons, including improved handling, easier cutting and less dust. Our manufacturing process ensures consistency during production, which results in reliable product quality.

Permeance: 0.02
R-value: 4.2
Recycle Content: 24%
Greenguard: Gold

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Available Documents

Microlite Standard duct wrap is made from flame attenuated fiberglass. It offers a high tensile strength core for improved handling and easy installation. Microlite Standard is available plain or vinyl-faced, and it can be used in applications where a vapor barrier is not required.

Johns Manville Microlite® Standard is a duct wrap made from flame attenuated glass fibers that delivers a high tensile strength core for improved handling and easy installation. It is available in plain or vinyl faced options and can be used where a vapor barrier is not required. This product provides a solution for a variety of applications that require improved thermal and acoustical performance.

R Value (Vinyl Facing): 3.9 (1.5")
R Value (No Facing): 4.3 (1.5")
Permeance Rating (Vinyl Facing): 1.3

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Available Documents

Polyisocyanurate foam board designed to insulate rooftop ducts and HVAC equipment

The XSPECT® ISOfoam APF board is a closed-cell polyisocyanurate foam core bonded to a foil facer on both sides. It is a highly versatile insulation that can be used in a variety of mechanical and OEM applications, including rooftop ducts, appliances, HVAC equipment, refrigerated transportation, storage vessels, and railcars.

XSPECT ISOfoam APF board offers one of the highest R-values of any rigid insulation available, making it ideal for both hot and cold applications. The foil facer on the insulation operates as an excellent vapor-retarder, working in tandem with the closed cell foam to contribute to a tightly sealed system. Additionally, the lightweight foam makes it easy to fabricate and install.

R-Value: R-2.7 - R-26
Thickness: 1" - 4"
Sizes: 48"x96", 48"x108", 48"x120"
Facings: Silver/Opaque

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Available Documents