Building Insulation Products Laminated EPS Insulation

Poly Shield® Fan-Fold

Poly Shield® Fan-Fold is an insulation and underlayment that reduces application labor costs while adding R-value to your exterior walls or roof. Each bundle is folded accordion style for easy transport and then rapidly unfolded to cover a 4 x 50 ft area.

Poly Shield® Fan-Fold is made of premium expanded polystyrene (EPS) rigid insulation that meets or exceeds the requirements of ASTM C578, Standard Specification for Rigid, Cellular Polystyrene Thermal Insulation. The core EPS is composed of closed cells with excellent dimensional stability, compressive strength, and water resistance. Poly Shield® Fan-Fold is faced with tough polymeric laminates on both sides for added strength and durability in storing, handling, and installation. Several different poly facer options are provided to meet project needs.

Fan-fold insulation showing accordion-like folds
Fan-fold insulation in a roof assembly

Facer Options

Poly Shield® Fan-Fold - Standard

Our standard Poly Shield® Fan-Fold is heat laminated on both sides with a printed polypropylene facer.

Poly Shield® Fan-Fold - Reflective

Poly Shield® Fan-Fold - Reflective is heat laminated on one side with a printed polypropylene facer and on the other side with a metalized, reflective facer. Properly installed with a dead air space, the reflective facer can provide a significant R-value boost to Poly Shield’s thermal performance.

Poly Shield® Fan-Fold - Polyester

Poly Shield® Fan-Fold - Polyester is heat laminated on one side with a printed polypropylene facer and on the other side with a polyester facer printed with "This Side Up." This facer is used in roof assemblies for compatibility with certain roof membranes.



Poly Shield® Fan-Fold is frequently used on exterior walls as an insulative backer board for siding, but also to insulate interior or basement walls.


As a roofing underlayment / re-cover board, Poly Shield® Fan-Fold significantly reduces application labor costs. It is also lighter weight and costs much less than most other roofing re-cover boards. This insulation is ideal for low-slope commercial and industrial roofs that employ mechanically attached or ballasted roofing systems, and may be part of Class A fire rated roof assembly. Poly Shield® Fan-Fold is bundled accordion style, with each bundle covering 200 ft2 or two squares.


Labor and Material Savings

Covering 200 ft2 in a lightweight bundle, Poly Shield® Fan-Fold can be installed far quicker than competing 4 x 8 ft insulation or backer boards.

Premium Quality

The EPS core of Poly Shield® Fan-Fold meets or exceeds ASTM C578 specs, with excellent dimensional stability & compressive strength.

Stable R-value

The R-value of EPS is permanent because the only gas in EPS is air. Unlike Polyiso or XPS whose blowing agents outgas and therefore lose R-value, EPS R-values do not degrade over decades of use.

Moisture Resistant

Cellofoam EPS is quick drying and does not readily absorb moisture from the air. Its closed-cell structure reduces the absorption and migration of moisture, and the facers surfaces are nearly impervious to moisture. Not a vapor barrier.

Environmentally Friendly

Cellofoam EPS contains no formaldehyde or ozone-depleting CFCs or HCFCs. Its EPS core is 100% recyclable and may contain recycled material.

Code Approvals

Underwriters Laboratory Listed, UL ER7260, for interior and exterior walls. UL Classified TGFU.R7260, UL ER7260, for low slope mechanically attached or ballasted roof systems. Part of a Class A assembly over noncombustible decks. Please consult local building codes and membrane manufacturers for system requirements.

Manufactured to your Needs

Poly Shield® Fan-Fold is available in 2 square bundles of 4 x 50 ft, in thicknesses of 1/4”, 3/8", 1/2”, and 3/4” and ASTM C578 nominal densities of 1.0, 1.25, and 1.5 lb/ft3.


Protect what matters most

We’re dedicated to manufacturing products that meet the highest standards of quality and performance. Need to know if Cellofoam’s products are right for your next project? Reach out to our team.