Your Best Choice for a Reliable Air Barrier Solution

SkyFlex™ is a tough, flexible air barrier for use in residential and commercial building applications. The product consists of two layers of aluminum deposited on a layer of woven polyethylene. When exposed to air films or enclosed air spaces in building cavities, SkyFlex’s low-emittance exterior layers reduce radiant heat transfer.

Fast Facts

  • Available for residential and commercial applications
  • Flexible for fast and easy installation
  • Adds R-value to building envelope Economy and high-performance options
  • Available in 500 square foot rolls in 48″ or 51″ widths

An Effective Air and Vapor Barrier

SkyFlex™ is designed to be used as a primary air enclosure boundary between conditioned and unconditioned air in the building envelope. Air barrier materials are measured by air permeance. An air barrier permeance equal to or less than 0.02L(sxm2)@75 Pa, as tested in accordance with ASTM 2178, qualifies as an air barrier material. It’s air permeance levels fall below 0.02L(sxm2)@75 Pa, making it a very effective air barrier material. As a Class I vapor retarder, this product also effectively reduces vapor permeability. SkyFlex™ has a vapor permeability of 0.01 perms making it an effective vapor retarder.

Improving Thermal Resistance

When installed in walls, ceiling or floor joists, SkyFlex™ low-emittance exterior layers can boost the wall system’s R-value or thermal resistance. When used for one side exposed to the attic, SkyFlex™ adds a R-1.7. When 0.75 inches is installed in an enclosed air space, the product adds R-2.9; for 1.50 inches of SkyFlex™, the added R-2.6 can be calculated using the ASHRAE book of fundamentals.

High-Performance Features and Benefits

  • Premium Flexible Sheet Air Barrier
  • Low-e Surfaces Reduce Radiant Heat Transfer
  • Inner Woven Layer for Superior Strength & Durability
  • Tough, Puncture-Resistant Material wont Tear
  • Provides R-value with Enclosed Air Spaces
  • Applications include: Bonus Room Knee Walls, Behind Tubs & Showers, Fireplace & Duct Chases, Elevator Shafts, Stairwells, Between Multi-Family Units, Between Garage & Living Spaces
  • 48″ or 51″ widths
  • 500 sq. ft. Rolls
  • Easy to Handle
  • Installs 2x Faster than Rigid Air Barriers
  • 1 Roll = 16 Sheets of 4 ft x 8 ft Board Product
  • Wider Rolls Reduce Seams
  • Meets ASTM C 2178 Air Permeability
  • Class A Flammability Rating
  • Supports Sustainability Goals
  • National Network of Insulation Distributors and Contractors
  • Improves Thermal Performance of Building Envelope
  • Significantly Improves Comfort in Living Areas with Exposed Walls
  • Reflects Heat Away to Keep Home Cooler in the Summer
  • Reduces Heat Loss to Keep Home Warmer in the Winter
  • 1 Roll = 16 Sheets of 4 ft x 8 ft Board Product
  • 1 Pallet covers as much as 2 pallets of Rigid Board
  • Fewer Seams Reduces the Chance for Air Gaps
  • Overlap Does Not Create the Thickness Problems of Rigid Board Barriers
  • Easier for Installers to Carry
  • Easier to Fit and Install in Small Spaces vs- Rigid Board
  • Installs with a Staple Hammer
  • Installs 2x Faster than Rigid Air Barriers
  • Save Labor
  • Save Warehouse Space
  • Save on Material & Shipping
  • Secure Fiberglass Batts for Better Performance Over Time
  • Increase R-value and Energy Efficiency When Used with Other Insulation such as Batt, Gypsum or Spray Foam
  • Adds R-1.7 with one (1) Side Exposed to Attic
  • Adds R-2.9 with 3/4″ Enclosed Air Space3
  • Protects Against Heat and Humidity
Width of Roll Solid – 48″ / 51″
VT – 48″
Diameter Solid – 5″
VT – 5″
Lineal Footage Solid – 125′ / 118′
VT – 125′
Coverage (Sqft) Solid – 500
VT – 500
Weight (lbs) Solid – 10
VT – 10
Test Method Description Results
ASTM E2178 Air Permeability Solid – <0.02 L/(s•m²)@75 Pa
VT – <0.004 L/(s•m²)@75 Pa
ASTM E96 Water Vapor Permeance Solid – <0.1 VT – >10
ASTM C1371 Emissivity Solid – 0.05
VT – 0.20
ASTM E84 Flame Spread Solid – <25
VT – <25
ASTM E84 Smoke Developed Solid – <50
VT – <50
Wall Exposed to Attic Solid – R-1.7
VT – R-1.4
0.75″ Enclosed Air Space Solid – R-2.9
VT – R-2.0
1.50″ Enclosed Air Space Solid – R-2.6
VT – R-1.8
Aluminum Foil 0.03 – 0.05
Other Low-e Material 0.11 – 0.25
Other Common Building Materials
including wood, masonry and
standard mass insulation
0.82 – 0.90
  • Meets International Building Codes (IBC)
  • Meets International Residential Codes (IRC)
  • Meets International Energy Conservation Codes (IECC)
  • Meets Florida Building Codes (FBC)
  • Meets Florida Residential Codes (FRC)
  • Meets Florida Energy Conservation Codes (FECC)
  • Third-Party Verified Code Compliance, IAPMO UEL 5003


  • AIA MasterSpec

    185 KB | DOC

  • SkyFlex™ CSI 3-Part Guide Specification

    32 KB | DOCX

  • SkyFlex™ Application Sheet

    515 KB | DOC

  • Skyflex™ Specification Sheet

    28 KB | PDF

  • SkyFlex™ IAPMO UEL 5003

    353 KB | PDF

  • SkyFlex™ Installation Sheet

    8 MB | PDF

  • Florida Commercial Building Code 2020 – FAQs

    232 KB | PDF

  • Florida Residential Building Code 2020 – FAQs

    203 KB | PDF

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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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