Maximize Your Walls with HY-Fi®: The Innovative Hybrid Insulation Solution

HY-Fi® is a cutting edge hybrid insulation product that provides a very cost-effective approach to creating high R-value walls. The hybrid insulation system combines low emittance surfaces and enclosed air spaces. When used in combination with traditional insulation, such as fiberglass batts or spray foam, it creates a superior insulating system at an unmatched price point. HY-Fi® is an especially attractive solution in areas with stringent building codes as it provides insulators and builders with a versatile, low cost, and easy to install hybrid system that achieves R-21 in small wall spaces.

HY-Fi® insulation addresses the dominant form of heat transfer — radiation — with layers of high reflectance and low emittance materials. This configuration creates three reflective air spaces between the interior wall and traditional insulation that adds an additional R-8 to the wall — which can reduce the amount of spray foam or fiberglass batts needed to achieve the desired R-value.

High-Performance Features and Benefits

  • Multi-Layer Hybrid Insulation System
  • Outer Layer of Kraft Paper Coated with Polyethylene
  • Inner Layer of Premium Grade Aluminum Foil
  • Plus Additional Layer of Foil Reinforced with Fiberglass Scrim
  • FI-FOIL® Expander Technology Separates Paper and Foil Layers
  • Creates Three (3) Reflective Air Spaces
  • Low-e Surfaces Reduce Radiant Heat Transfer
  • Quick Installation with Staple or Tape Tab
  • 16″ or 24″ widths
  • Perforated or Solid
  • 500 sf Rolls
  • Combine with Spray Foam or Mass Insulation
  • Achieve R-21 using HY-Fi System of 2″ R-6.75 SPF with 1-1/2″ Enclosed Air Space
  • Achieve R-22 using HY-Fi with 4″ R-3.7 SPF with 1-1/2″ Enclosed Air Space
  • Add R-7 or more Using HY-Fi with Batt or Foam Insulation
  • Verified Recycled Content >28%
  • Supports Sustainability
  • Add up to R-7.1
  • Third-Party Verified Code Compliance, IAPMO ER 358
  • Lightweight 500 sq ft Rolls
  • Easy to Handle, Installs Faster
  • Less Waste on Site – No Shaving SPF
  • Less Waste in Landfills – Better for the Environment
  • Air Space in Cavity Allows for Last Minute Changes to plumbing or wiring
  • Save Labor
  • Save Warehouse Space
  • Save on Material & Shipping
  • High Performance and Compact
  • Provides for More Living Area Square-Footage for Increased Marketability
  • Low-e Reflective Surfaces Improve Performance of Enclosed Air Space
  • Maximize Comfort
  • Maximize Energy Efficiency
  • Used on Net Zero Building Projects
  • Supports Sustainable Design Goals
  • Specified in the NAHB New American Homes 2017, 2018
  • Specified in the NAHB New American Remodel 2019
  • Lowers HERS® and Other Energy Rating Indexes (ERI)
  • 10-Year Warranty
  • National Network of Insulation Distributors and Contractors
Furring/Stud Spacing 16″ O.C 24 O.C
Width Expanded 17.5″ 25.5″
Diameter 12″ 10″
Lineal Footage 375′ 250′
Coverage 500 sq. ft. 500 sq. ft.
Weight 29 lbs 27 lbs
2″ x 4″ Frame Wall Hy-Fi™ with 2″ R-6.75 Spray Foam R-21
2″ x 6″ Frame Wall Hy-Fi™ with 3.5″ R-13 Fiberglass R-21
Test Method Description Results
ASTM E-96 Water Vapor Permeance 0.20
Water Vapor Permeance Hi-Perm 5.42 perms
ASTM E-84 Flammability Flame Spread Rating: 20
Smoke Development Rating: 10
Interior Wall & Ceiling Finish Classification: Class A
ASTM D-3310 Corrosivity None
ASTM C-1224-99 (9.2.1 & 9.2.2) Adhesive Performance Bleeding: None
Delamination: None
Pliability: No signs of cracking or delamination
ASTM C-1338 Mold & Mildew Pass
ASTM C-1371 Foil Emittance 0.034

Ensuring Code Compliance with HY-Fi Insulation

  • Meets or exceeds ASTM C1224, the Standard Specification of Reflective Insulation.
  • Meets International Building, Residential and Energy Codes.
  • Meets Florida Building, Residential and Energy Conversation Codes.
  • IAPMO Evaluation Report number 0358
  • Meets ASTM C 1224, Reflective Insulation
  • 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)


  • HY-Fi® Submittal Package

    25.20 MB |

  • AIA MasterSpec

    185 KB KB | DOC

  • HY-Fi® CSI 3-Part Guide Specification

    29 KB | DOCX

  • HY-Fi® Brochure

    18 MB | PDF

  • HY-Fi® Specification Sheet

    1 MB | PDF

  • HY-Fi® System R-Values for Above Garage Ceiling Assemblies

    142.24 KB | PDF

  • HY-Fi® Installation Sheet

    2 MB | PDF

  • HY-Fi® Safety Data Sheet

    108 KB | PDF

  • Recycle Verification Report 2023 Q3

    237 KB | PDF

  • HY-Fi® Frame Floor with Hybrid Insulation System [DWG]

    28 KB | ZIP

  • HY-Fi® Frame Floor with Hybrid Insulation System [PDF]

    69 KB | PDF

  • HY-Fi® Frame Floor with Hybrid Insulation System [RVT]

    1,009 KB | ZIP

  • HY-Fi® Frame Wall with Hybrid Insulation System [DWG]

    31 KB | ZIP

  • HY-Fi® Frame Wall with Hybrid Insulation System [PDF]

    73 KB | PDF

  • HY-Fi® Frame Wall with Hybrid Insulation System [RVT]

    1,012 KB | ZIP

  • Florida Commercial Building Code 2020 – FAQs

    232 KB | PDF

  • Florida Residential Building Code 2020 – FAQs

    203 KB | PDF


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.
The “tested” value is for specific dimensions – specifically the air space between the Hy-Fi and foam. The tested precision is about +/- 10%. In view of this, the agreement between the calculated and “tested” values are quite good. Hy-Fi adds R-7.1 to the insulation assembly with a 1.5″ air space.
Reflective insulation has little effect on heat transfer by conduction through the air between hot and cold surfaces. Air with an R-per-inch of 5.6 is an excellent insulator when radiation and convection are controlled. The installation of reflective insulation in an enclosed space reduces thermal radiation to near zero. When the reflective insulation is installed to subdivide an air-filled region then convection is also reduced.

Hy-Fi is the hybrid insulation system combining spray foam insulation with VR Plus Shield Reflective Insulation. This system defends against all forms of heat transfer at a reasonable price.

A reflective insulation below the roof deck results in an interior surface temperature that is greater than the outside temperature (in cold weather). As the inside surface temperature increases, the conditions for condensation become less likely to occur.
30 minutes is the best waiting period before installing Hy-Fi. As the spray foam cures, moisture is released through an exothermic reaction (looks like steam). It is best to allow this moisture to escape before installing HY-Fi®.
Reflective insulation is one or more low emittance surfaces installed in an enclosed air space. The more layers within the air space, the better the performance. Reflective insulation in a wall system can be compared to a double or triple pane window with low-e surfaces. Triple pane windows with low e surfaces perform better than a triple pane window without low e surfaces because of the reduction of radiation (low emittance) across the air spaces. Air inherently has an R-per-inch value of 5.6, and is an excellent insulator when radiation and convection are controlled. The ASHRAE Handbook has tables with values for various enclosed air spaces (0.5”, 0.75”, 1.5”, 3.5”, etc.) with high emittance surfaces (0.82 for common building materials) and values for air spaces with low emittance surfaces facing the enclosed air space (0.05 for low emittance materials like aluminum). Simply put, adding a low e material makes the enclosed air space perform better. A multilayer reflective insulation system in a wall cavity improves this system by further reducing radiant heat transfer and adding additional “panes”, a two layer reflective insulation could be compared to a double paned window; a three layer to a triple pane window, and so on.. The installation of reflective insulation in an enclosed space reduces thermal radiation to near zero. When the reflective insulation is installed to subdivide an air-filled region then heat transfer by convection is also reduced. Fi-Foil has single layer, two layer, three layer and even honey-comb layer reflective insulation products for various building applications, each with different performance levels and attributes for the particular application. These products also work very well with other types of mass insulation as hybrid systems by using the best attributes of each of the technologies (e.g. spray foam is great for air sealing and can have a high R–value per inch of thickness — fiberglass and cellulose is an inexpensive material to reduce convection in the cavity). In some wall systems, especially wall cavities larger than 1.5”, a combination of reflective insulation with one or more of these mass insulation products, addresses all the modes of heat transfer — often more cost effectively than one of the technologies used alone.

The R-value for a reflective air space depends on the temperature difference across that air space. The temperature across the air space depends on the r-values in the system since the bounding temperatures are fixed.

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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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