FSK-faced Fiberglass Duct Wrap
This information reflects our best understanding of product composition in 2016.
Fiberglass duct wrap is a fiberglass blanket that is applied to the exterior surface of metal duct work to reduce heat transfer and control moisture condensation. The duct wrap is typically faced on one side with an FSK (foil-scrim-kraft) facing....
Fiberglass duct wrap is a fiberglass blanket that is applied to the exterior surface of metal duct work to reduce heat transfer and control moisture condensation. The duct wrap is typically faced on one side with an FSK (foil-scrim-kraft) facing. The overlapping seams of the facing are stapled to hold the insulation in place, and when a vapor barrier is required, seams are sealed with pressure sensitive tape or glass fiber fabric and mastic. The percent composition in this CP is based on a 3" thick, Type 75 insulation with an installed R-value of 8.3. Duct wrap comes in a range of R-values, thickness, and density which would vary in the percentages of each component within the insulation and higher density products may use a different binder. Most manufactures are using a formaldehyde-free binder, but wrap with formaldehyde-based binders is still available. This may be more prominent for the higher density products. Typically, these products contain from 16-50% or greater post-consumer recycled content and are GreenGuard Gold certified. The insulation industry provides very little disclosure for FSK-faced duct insulation blanket. This CP assumes that the FSK facing is bound to the insulation using the same asphalt-based adhesive used to adhere paper to standard fiberglass blanket insulation.