EcoFoil Reflective Foil vs. Fiberglass Insulation

Conventional fiberglass insulation has set the standard in the building industry for many years. Fiberglass insulation has been around since the late 1800's and typically comes as rolled insulation or batt insulation. Another type of fiberglass insulation is loose fill-blow in insulation for use in attics. All fiberglass insulation gets its effectiveness from its thickness and density. The effectiveness of fiberglass insulation is measured by R-Value. R-Value, also referred to as R-factor, measures the amount of heat transfer per inch of insulation material. Heat is transferred in 3 different ways...Convective Heat Transfer, Conductive Heat Transfer and Radiant Heat Transfer. To learn more about these modes of heat transfer visit our Reflective Foil information page: How Radiant Barrier Foil Works. Considering the fact that radiant heat is the primary method of heat transfer and r-value does not measure radiant heat transfer, r-value is not always a reliable measurement for thermal value in an assembly.

EcoFoil and R-Value

EcoFoil will stop 97% radiant energy (heat that is radiating through the air). Radiant heat is often overlooked and misunderstood because r-value does not account for radiant heat. Radiant heat transfer is responsible for up to 75% of a buildings total heat gain or loss. Traditional insulation products such as fiberglass, cellulose and foam board are effecive in reducing convection and conduction, but do little to prevent radiant heat transfer. Radiant heat energy can either be absorbed or reflected.  EcoFoil contains metalized aluminum which has high reflective properties making it very effective against radiant heat transfer.

Disadvantages of Fiberglass insulation

There are many disadvantages to using fiberglass insulation. If you look at the warning label on a bag of fiberglass insulation it advises you to avoid contact with any part of your body and most importantly to wear breathing protection. The composition of fiberglass insulation includes a variety of inexpensive resources like recycled glass and limestone. Installing fiberglass batt Insulation is very itchy and uncomfortable. Also, fiberglass insulation should not be used in high humidty areas because once it gets damp or wet it loses much of its effectiveness and can form harmful mold.  A vapor barrier must be installed between fiberglass insulation if it separates a warm surface from cool air or vice versa.

  • Fiberglass insulation is hazardous to lungs and skin
  • Fiberglass batts will not seal without additional vapor barrier
  • Fiberglass batt insulation does not stop radiant heat transfer
  • Loses effectiveness due to settling or compressing
  • Humidity causes it to lose its effectiveness if not sealed properly
  • Must install an additional vapor barrier for moisture protection
  • Fiberglass insulation acts like a sponge, absorbing water
  • Wet fiberglass insulation is likely to form dangerous mold

Dangerous Black Mold on Fiberglass Insulation in Stud Wall

 Harmful mold on Fiberglass Insulation in Stud Wall  

Mass insulation is neccessary in most parts of the country in order to create an overall efficient thermal value in a structure. We are not trying to lead you to believe that Foil Insulation can replace all mass insulations. We are just informing you of the facts pertaining to the different ways that heat can be gained or lost in a structure and to show you how to use Foil Insulation properly whether it's used with or without mass insulation. Keep in mind that there are many new forms of mass insulation that are much less harmful and safer to use than fiberglass insulation.

Advantages of Reflective Foil Radiant Barrier

  • Strong but lightweight 
  • Clean and easy to install
  • Can be used alone or installed with other forms of insulation
  • Unaffected by humidity and moisture
  • Provides a vapor barrier
  • Low emissivity (.03)
  • High reflectivity (97%)
  • Excellent longevity, will not lose it's performance
  • Installs faster and easier than fiberglass - can be stapled, nailed or glued
  • Safer to install, requiring no special clothing or breathing protection
  • Nontoxic, will not irritate the skin, eyes, or throat
  • Carries a Class 1 / Class A fire rating. (EcoFoil is proud to be the first to both offer a metalized aluminum radiant barrier and a product that passes the newest ASTM E84-2009 fire test.)
  • Forms as a radon barrier when used for ground applications
  • Creates a nice finished appearance when left exposed
  • Saves energy and money all year around

Reflective foil insulation blocks 97% of the radiant heat transfer as well as forming a thermal break or vapor barrier.  Simply stated, foil radiant barrier reflects heat and fiberglass insulation only resists heat.  Reflective insulation keeps hot sun from invading your cool air space in the summer and keeps warm furnace air from escaping your home in the winter.