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Kingspan Kooltherm – R-8/in?

CMOD | Posted in Green Products and Materials on

Recently got sent a sample and some information on a new ‘premium’ rigid foam Kingspan is trying to market in the US after making it in Europe for quite a while. A little googling and this appears to be some sort of phenolic foam, maybe. Some of the claims in the literature have me scratching my head:

-R-8/inch. Seems awfully high for rigid foam. They claim this is from an ASTM C 518 test but the rep wouldn’t send me the actual report.

-Higher R-Value per inch in thicker panels. They claim a 1.575in panel is R-12 (7.62/in) and a 2.362in panel is R-19 (8.04/in). Is that even possible in a closed cell foam?

-Different facers change the R-value. At first I thought this was the usual radiant foil silliness, but when I pressed for details the rep said the glass/glass facer was best by about 3%, and again wouldn’t send me the report. I am assuming this is due to the fiberglass facer being slightly thicker than the foil, and 3% is in ‘who cares’ territory anyway. Not sure why they’re marketing on that though.

The sample kind of reminds me of the foam they stick flowers in – stiff, makes a crackling sound when you press your finger into it.

Anybody have any experience with this yet? Price?

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  1. CMOD | | #1

    I'm not sure why the thumbnail shows a floorplan... image is correct when clicked though.

  2. GBA Editor
    Martin Holladay | | #2

    It's a web site glitch -- if you choose a common word as the file name for your image (something like "Capture" or "Image 1") then our web site will post a thumbnail from a previously posted image with the same name.

    I've renamed your image, so it should work now.

    -- Martin Holladay

  3. GBA Editor
    Martin Holladay | | #3

    It turns out that there is a report (available online). Here is the link:
    Intertek Code Compliance Research Report CCRR-1066.

    I am reproducing the table showing the results of the R-value testing below.
    Note that 25 mm = 0.984 inch and 75 mm = 2.95 inches.

    According to the table, Intertek is reporting that the 75 mm products have R-values ranging from R-8.06 per inch to R-8.44 per inch.

    -- Martin Holladay


  4. CMOD | | #4

    Martin- Thanks.

    I'm still really curious how a 3x thicker product has 3.8x the R-Value (looking at the K10)

    Also, that report oddly lists that "in exterior walls, use of the insulation boards is limited to Type V construction..." Type V is the least restrictive - if it's OK to use on combustible framing, I can't think of a reason why you couldn't use it on Type I-IV.

  5. GBA Editor
    Martin Holladay | | #5

    Like you, I have several unanswered questions. I'm looking into those questions now. I'll report back as soon as I learn something.

    -- Martin Holladay

  6. AlanB4 | | #6

    If you need another bug to add to the list the replies go from 2 to 4.

  7. GBA Editor
    Martin Holladay | | #7

    Not a bug. After I posted my Comment #4, I deleted my Comment #3, which was based on incomplete information.

    -- Martin Holladay

  8. AlanB4 | | #8

    I guess your software does not have dynamic numbering?

  9. GBA Editor
    Martin Holladay | | #9

    It's better if the numbering isn't dynamic. That way, I can refer to "Comment #16" without worrying that a future deletion will change the comment to #15.

    -- Martin Holladay

  10. AlanB4 | | #10


  11. nick_vk | | #11

    While you are at it Martin, check out the claims for the OPTIM-R product:

    Kingspan OPTIM-R is an optimum performance next generation insulation product. It is a rigid vacuum insulation panel comprising a microporous core, which is evacuated, encased and sealed in a thin, gas-tight envelope to give outstanding R-values, and an ultra-thin insulation solution.

    With an R-value as high as R-56.782 for a 2″ panel thickness, Kingspan OPTIM-R provides an insulating performance that is up to 5 x better than other commonly available building insulation materials. The high level of thermal efficiency with minimal thickness, achieved by Kingspan OPTIM-R, can provide solutions for applications where a lack of construction depth or space is an issue.

  12. iLikeDirt | | #12

    Well it's a vacuum panel, so that makes sense. Vacuum panels work, but they're just really fragile and lose all their insulating power if broken.

  13. GBA Editor
    Martin Holladay | | #13

    Nick and Nate,
    I'm pretty sure that Chris B's original question wasn't referring to a vacuum insulated panel (V.I.P.). Although Kingspan may make VIPs, the products that I looked up aren't VIPs. Here is the description in the lab report for the products whose R-values are listed in the table I posted:

    "Kooltherm® K15, K8, K7, and K12 Insulation Boards are phenolic foam core insulation boards with composite foil facers on both surfaces. Kooltherm® K10 Insulation Boards are phenolic foam core insulation boards with a glass fiber tissue-based facing on the back surface and a composite foil facer on the exterior surface. Kooltherm® K20, K5, and K3 Insulation Boards are phenolic foam core insulation boards with a glass fiber tissue-based facing on both surfaces. The Kooltherm® insulation boards are supplied in thicknesses ranging from 25mm to 75mm, except for Kooltherm® K10 which is supplied to a maximum thickness of 120mm."

    -- Martin Holladay

  14. BillDietze | | #14

    Even if it's real, what's the aged R value? What's the blowing agent? Some demilac products claim increased R value per inch as the foam layer gets thicker. The Heatlok HFO high lift is rated at R 7.5 per inch at 4" thick, aged value. So if this is similar and the R 8 per inch is the initial value, then it's believable....ish!

  15. bluesolar | | #15

    Martin, chiming in late here because of Google... Nick was referring to Kingspan's OPTIM-R product, which are VIPs. Nate was highlighting that they're VIPs.

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