The Many Facings of Fiberglass Insulation

FSK, PSK, ASJ, poly-top and vinyl are all common insulation facing terms you may have heard referenced within the insulation industry. At the most basic level, these terms relate to the external, protective surface-facing or jacketing on insulations used for pipes or HVAC ductwork. Facings and jacketings serve several purposes in air handling and piping applications, including helping your system meet building codes, achieve better energy efficiency, and control condensation – just to name a few. We hope that this blog will be able to help you better understand the differences between the facings and jacketings used within the insulation industry today. 

First off, let’s take a look at FSK facing, or foil-scrim-kraft. Foil-scrim-kraft is a flame retardant, vapor-barrier, and it is one of the most commonly used facings in the insulation industry today. During the manufacturing process of an FSK facing, a layer of lightweight aluminum foil is layered against a tri-directional, reinforcing fiberglass scrim (yarn) and then paired with a final layer of natural brown kraft paper. This is all laminated together using a flame-retardant adhesive.

Click here to read more about facing options for fiberglass insulation.