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A new low for radiant barrier misstatements

Martin Holladay | Posted in Green Products and Materials on

Don’t you love radiant barrier websites? They are a constant source of amusement. My latest favorite stupidity comes from the EnergyFoil website, which helpfully defines R-value. Are you ready?

“An example would be a product with an R-Value of R-19 which means that it will take about 19 hours for the temperature on the inside to become the same as the temperature outside. R-38 = 38 hours, R-11 = 11 hours, etc.”

And all these years, I mistakenly thought that R-value was 1/U.

Guess what? The website displays the RESNET logo and the Energy Star logo at the bottom of the page.

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  1. dankolbert | | #1

    They're just teaching the controversy.

  2. GBA Editor
    Martin Holladay | | #2

    Well, as least they introduced the topic on the right note. The strange statement begins, "Factual information can actually be pretty hard to find. Radiant barriers are surrounded by stigma, myths, and misconceptions..."

  3. dankolbert | | #3

    The medium is the message. Or something like that.

  4. wjrobinson | | #4


    Time to Temperature Value

    With a TTV-60 one has a highly insulated structure.

    TTV,=~R in people speak....

  5. [email protected] | | #5

    Apparently factual information is very hard to find when dealing with the radiant barrier crowd.

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