Insulation Finishes—This Month’s Topic: Laminates

January 1, 2014

Characteristics of Weather Barriers,
Vapor Retarders, and Finishes

Laminates are, in general
terms, materials made by bonding
(through the use of heat, pressure,
adhesives, or any combination thereof) 2
more layers of materials. The layers can
be comprised of similar or dissimilar
materials. Laminates used for protective
jacketing may be comprised of metal
foils, plastic films, papers, nonwovens,
scrims, etc. and may or may not
contain a topcoat of some kind for
coloration or UV resistance. Laminates
also come in a variety of different

For vapor retarder
applications, at least 1 component must
be a material that offers significant
resistance to vapor passage.
Laminates may be classified into 3

  • Laminated Foil
    Jacketing (ASJ/FSK/PSP/PSK)

  • Synthetic Rubber

  • Multi-ply

Laminated Foil Jacketing

traditionally used
pre-formed jacket for pipe, tank, and
equipment vapor retarder applications is
the lamination of white paper,
reinforcing fiberglass scrim, and
aluminum foil.
This laminate is typically called All-
Service Jacket (ASJ). Variations on this
sometimes referred to as Next Generation
ASJ, is a similar basic structure,
with a white polymer film/substrate in
place of the bleached paper. These
are generally referred to as ASJ or next
generation ASJ  and meet the
of ASTM C1136, Standard Specification
for Flexible, Low Permeance Vapor
Retarders for Thermal Insulation.
Traditional ASJ or next generation ASJ
facings are commonly used as the outer
finish in low abuse, indoor areas;
elsewhere, they are covered by a
protective metal or plastic jacket.

similar facing
material, foil-scrim-kraft (FSK) has the
same basic structure except with the
aluminum foil layer facing outward.
Numerous variations, such as Poly-Scrim-
(PSP) or Poly-Scrim-Kraft (PSK), are
also available. Many types of insulation
products are supplied with factory-
applied ASJ, FSK, or PSK vapor

Synthetic Rubber

Synthetic, rubber-
laminates typically consist of aluminum
facing laminated to a synthetic rubber
membrane and a peel-and-stick
application. These laminates are used on
ducts, and tanks for both interior and
exterior applications, and may be used
in direct burial applications. A variety
of weights are available. Perm values
of less than 0.02 are reported, and the
materials are generally considered to
be “self-healing” in that small
punctures and penetrations will re-seal.


laminates consist
of multiple layers of aluminum with
alternating layers of polyester or
polyethylene film with a peel-and-stick
adhesive system. These laminates are
used on pipes, ducts, and tanks for both
interior and exterior applications.
They cut easily and install easily in
the field. Perm values of 0 or near 0
reported. They are available in smooth
or embossed surface finish in a variety
of thicknesses. Several colors and
chemical-resistant films are also