A Safe and Effective Insulation Choice for Fire Protection

FSK Shield™ is a single-sided foil facing comprised of aluminum foil bonded to natural kraft paper with a flame retardant adhesive and reinforced with tri-directional fiberglass scrim.

FSK Shield™ is intended as a class A for >25 FS insulation facing. The product also can be used as an effective vapor retarder.

The aluminum facing also reduces radiant heat transfer for added R-value or as a radiant barrier and is available in 1000 square foot rolls 54″ wide.

Why FSK Shield™ Outperforms

  • Class A Insulation Facing
  • Ideal for Unfaced Batts
  • Can Be Used as Radiant Barrier for Attics, Roofs and Walls
  • Low-e Aluminum Foil Bonded to Natural Kraft Paper
  • Reinforced with a Tri-Directional Fiberglass Scrim
  • 54″ width
  • 1000 sq. ft. Rolls
  • Class A Flammability Rating
  • National Network of Insulation Distributors and Contractors
  • Adds R-4.6 to an Exposed Roof or Ceiling Application
  • Cost-Effective Method to Meet Code Requirements for Flammability
  • Replaces Expensive Foil-Faced Batts
  • Increases Thermal Resistance for Better Performance
  • Easy Handling & Installation
Width of Roll 54″
Diameter 5″
Lineal Footage 222′
Coverage 1000 sq. ft.
Weight 25 lbs
Test Method Description Results
ASTM E-96 Water Vapor Permeance 0.02
ASTM E-84/UL 723 Surface Burning Kraft Exposed Flame Spread Rating 25
Kraft Exposed Smoke Developed Rating 10
Foil Exposed Flame Spread Rating 5
Foil Exposed Smoke Devlopment Rating 0
FSK Shield & Unfaced Batt Flame Spread Rating 15
Smoke Developed Rating 0
ASTM E-408 Emissivity 0.03
ASTM D-828 Tensile Strength (lbs/in) MD: 40
XD: 25
Scrim pattern per lineal inch MD 2
XD: 3
ASTM D-774 Mullen Burst Strength 40 psi
ASTM C-1136 Mold & Mildew Pass
Dimensional Stability Percent Length Change 0.25%
Low Temperature Resistance No Cracking or Delamination -40F
High Temperature Resistance No Cracking or Delamination 240F
Puncture Resistance Beach Puncture Units (Joules) 25
See IAMPO ES Report #0291

FSK Shield™ Safety Codes and Compliances

  • Meets ASTM E-84
  • Third-Party Verified Code Compliance, IAPMO ER 291


  • AIA MasterSpec

    185 KB | DOC

  • FSK Shield™ CSI 3-Part Guide Specification

    29 KB | DOCX

  • FSK Shield™ Application Sheet

    8 MB | PDF

  • FSK Shield™ Application Sheet

    8 MB | PDF

  • FSK Shield™ Specification Sheet

    278 KB | PDF

  • FSK Shield™ Safety Data Sheet

    157 KB | PDF

  • FSK Shield™ Installation Sheet

    284 KB | PDF

  • Florida Commercial Building Code 2020 – FAQs

    232 KB | PDF

  • Florida Residential Building Code 2020 – FAQs

    203 KB | PDF


In a home without a radiant barrier at the roofline, your roof radiates solar-generated heat, which elevates attic temperatures upward to 150 degrees or higher. These higher temperatures will increase the heat gain in air conditioning ducts and reduce the performance of mass insulation (the R-values of mass insulation are determined at 75 degrees F – higher temperatures lower the R-value). In addition, the extreme temperatures will saturate the building materials in the attic. This stored heat acts as a heat sink and will continue to transfer heat into the living area of a home even after the sun has set, making the air conditioner run longer and consume more electricity. A radiant barrier stops 97% of radiant heat transfer, which improves the performance of insulating materials and lowers attic temperatures as much as 30 degrees F. A cooler attic will transfer less heat into your air conditioning ducts. Radiant barriers lower both cooling and heating costs, reducing energy expenditures throughout the year.
R-values relate more to mass type insulations or insulating materials that are installed in an enclosed air space. Radiant barriers are typically designed to work in vented attics, so their performance is not rated with an R-value; however, R-values are not the ONLY way to quantify resistance to heat flow. For example, a tree or an awning doesn’t have an R-value, but it certainly can keep you cool. To simply put it, a radiant barrier is like putting a shade tree in your attic. Technically speaking, Silver Shield™ Radiant Barrier reflects 97% of the radiant heat and only emits 3% into the attic so unlike R-value, the lower the “E-value”, or the less that it radiates into the attic, the better the radiant barrier. Silver Shield™ is the best-rated radiant barrier on the market.
A water vapor retarder may or may not be part of the design depending on the climate zone and the other building components used in that particular section of the building envelope. If air containing water vapor is allowed to come in contact with a cold surface, then condensation will likely occur. Water vapor transmission can also occur even if the building envelope is air sealed or has an effective and properly installed air barrier. Some insulation systems should include a water vapor retarder and some should allow vapor transmission. Building codes and climate zones generally dictate the use of a water vapor retarder — in short, the envelope is a system and the use should be carefully considered by the building designer.
As building envelopes are getting tighter, building scientists, energy centers and research organizations are suggesting that insulation products and facings used in hot humid climates have higher perm ratings for increased water vapor transmission. Fi-Foil’s Hi-Perm versions are designed to meet or exceed these recommendations.
These roofs are excellent reflectors of solar reflectance when new but over-time, as they age and get dirty, the reflectivity is lowered. Radiant barriers would still reduce whatever heat flow that penetrates the roof surfaces by the same percentage – there is just less heat coming through these types of metal roofing materials vs. a shingle roof. As the metal roof ages, and the metal reflects less solar radiation, the radiant barrier has a greater impact on energy savings.
Purchase one of the following products to boost your cell phone signal: From Verizon Wireless – 3G Network Extender (cost is approximately $249.00). From AT&T Wireless – 3G MicroCell (cost is approximately $200.00). Please understand there can be a variety of reasons for a weak cell phone signal, and the products above were recommended by the two top cell phone service providers.

A radiant barrier is a product that features a low emittance surface(s) (normally aluminum foil) that is designed to significantly reduce heat transfer between a very hot and high radiating surface (bottom of a roof deck) and a cooler highly absorbent surface (i.e. insulation on top of a ceiling). Multiple low emittance surfaces, even multiple layers with enclosed air spaces, can further reduce radiant heat transfer. Effective emittance is one term that can quantify the impact of the impact of the additional surfaces. In summary, the lower the emittance (radiation rate), the better the performance. Radiant barriers have been demonstrated to achieve significant energy savings in a wide variety of building types and in multiple climate zones.

To best increase your energy efficiency, you should deal with the problem at its source, the roof, and the best way to address it is by adding a radiant barrier. A radiant barrier is specifically designed for this application and will reduce heat transfer up to 97%. The radiant barrier will improve the performance of both the air conditioning ductwork and the mass insulation and will improve comfort in garages and patios, areas that are typically not conditioned. Studies have shown that the radiant barrier / mass insulation combination out-performs mass insulation alone. Silver Shield Radiant Barrier is installed just below the roof sheathing. The idea is to stop the heat right at the source, the roof, before it gets into the attic or building envelope. Standard mass insulation is almost always installed on the surface of the ceiling, and air conditioning duct systems are almost always installed in the attic space. So without a radiant barrier, the heat would build-up in the attic and reach extreme temperatures, upwards of 140 degrees. Think about it, does it make sense to pump 55-degree air through ducts running through a super-heated attic? And does it make sense to expose insulation to extreme temperatures when the R-value rating is determined at 75 degrees, with the knowledge that the R-value rating drops as the temperature increases? No, of course not! Why let the heat get in the attic in the first place? To summarize, adding a radiant barrier simply provides more benefits over adding more insulation (cooler attic, improvement in duct performance, improvement in ceiling insulation performance, more comfortable areas of the home that are typically not insulated like the garage and patio). If you have extra money in your energy budget, do both; however, the order is radiant barrier first, more ceiling insulation second.

Various studies including those conducted by the Florida Solar Energy Center have concluded that it would be highly unlikely. In the Sunbelt and specifically Florida, shingles are exposed to roof temperatures of 160 to 190 degrees. Studies have proven that radiant barriers only increase roof temperatures by 2 – 5 degrees. A few degrees more won’t make a difference.
Radiant barriers reduce heat gain (in the summer) and heat loss (in the winter), so it will benefit both winter and summer savings and comfort. In the summer, heat is reflected back to the outside and in the winter, heat is reflected inwards.
No, they work with or without ventilation but will perform better in ventilated attics. According to the building code, all attics in Florida must be vented. Extended Version: Studies have shown that with or without a radiant barrier, a ventilated attic is best and the same holds true for a radiant barrier. A house will perform better with a radiant barrier and a ventilated attic than a house with a radiant barrier and a non-ventilated attic. Houses must be designed to meet the building code, which has ventilation requirements with or without a radiant barrier. In both cases, it is the ventilation rate that is important, not the method or type of ventilation.
Yes, but it is a lot more costly due to labor. The time to consider it is in the new construction phase. There are many other energy upgrades, such as additional blown or batt insulation that can be easily added at a later date if current budget is a factor.
Heat radiates through the roof, and areas unprotected by the radiant barrier will allow heat to transfer to other areas of the house. Installing a radiant barrier in all areas of the house not only improves overall performance, but also increases comfort levels in unconditioned areas like garages and patios.

Condensation will occur on any surface when the temperature of the surface is at or below the “dew-point temperature” for an air-water mixture. The dew-point temperature depends on the dry-bulb temperature (measured with an ordinary thermometer) and the relative humidity in the space next to the surface. The dew-point temperature is less than or equal to the dry-bulb temperature. The two temperatures are equal when the relative humidity is 100%. Some examples of dew-point temperature:

radiant barrier temperature chart

As you can see, condensation can occur when the outside temperature is cold. Insulation below a roof deck will have an inside surface temperature that is above the roof surface temperature. The actual temperature of the inside surface depends on the amount of thermal resistance between the roof and the inside surface. The higher the resistance, the closer the interior surface temperature will be to the inside air temperature. Maintaining a reasonable inside relative humidity (less than 60%) is an important factor in preventing condensation.

post frame building ready for reflective insulation

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We manufacture, market, and distribute high-performance reflective insulation and radiant barriers. Our products are sustainable and improve building performance and comfort all year round. Our reflective insulation is one of the fastest-growing technologies in the world and we want you to grow with us.

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