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How to Tell If Cardinal Glass Has Correct Coatings & Is Right Thickness?

gordy_b | Posted in Green Products and Materials on

Glass Geeks,

After a few instances like the delivery of this fridge (attachment (I couldn’t get this question to send with the image in-line))…

… I always check the model and condition of incoming major deliveries.  For appliances, if the model number is correct, I know I’m getting the qualities I ordered.

BUT, non-stock, custom ordered insulated glass units from Cardinal are being delivered in the next week or so.  I imagine the specifications will be written up in the paper work.  How can I check those specs were actually followed?  As far as checking the glass thickness I believe I read it will be laser inscribed somewhere – does that sound correct???  Will the low-e and “self-clean” coatings applied be laser inscribed???  If not, is there any way to know the layers I ordered were applied???


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  1. mr_reference_Hugh | | #1

    From what I understand, Cardinal is the dominant player in the market. I would just call them and ask them. I can't imagine they have anything to hide. Look at the document at this link, it might be exactly what you are looking for.

  2. gordy_b | | #2

    mr reference Hugh,

    Thanks, I'll try to decipher the logo as per "Marking and Labeling of
    Laminated Glass." And if I can't, the glass and gap thicknesses can be measured I think. Besides the paperwork I don't see see a way to confirm the correct layers are on. My installer said there would be stickers indicating which surface is #1 and which is #4 - maybe the stickers will indicate which coatings are on.

    I don't think Cardinal is trying to hide anything. But, I've seen too many mistakes made to not want to physically verify the specifications are correct (in this case glass and gap thickness and coatings).

    1. mr_reference_Hugh | | #4

      Mistakes, I get it. I still question today whether my windows are what was in the contract but never wanted to know with certainty…. In my case it was …what you don’t know can’t hurt you. Good for you for checking.

    2. kyle_r | | #5

      On my windows the stickers did indicate which coating was applied. This is how I found out the window manufacturer ordered 272 instead of the 180 I specified. You are right to check.

  3. Expert Member
    BILL WICHERS | | #3

    You can measure the glass with a micrometer, so that part is relatively easy. To check the coatings, you'd need a variable wavelength light source and some kind of light meter. I've never actually tried to do that, but it would be possible to check. You'd need to measure the amount of light transmitted through the glass and compare it to the transmission charts for the various coatings.

    I would say "yes", you CAN check this, but it will take some specialized equipment to do reliably. For just a quick "is it coated?" sanity check, you could get a small piece of plate glass of the same thickness as the IGU panes, and visually compare it to the IGU. All of the coatings will make the coated glass appear slightly darker and tinted compared to a piece of uncoated glass, so this might at least give you some level of comfort that your IGU isn't completely wrong.


  4. gordy_b | | #6

    Thanks all. The IGUs arrived. If someone knows how to read Cardinal stickers and etchings, please tell me what stack up (coatings, glass thickness, gas fill (or not)) these IGUs are. For suspense I'm not saying yet what I ordered.


  5. [email protected] | | #7

    Where are these IG's coming from? Cardinal has 42 manufacturing plants around the US, with 11 factories that produce IG units. Although plant managers are allowed a good bit of discretion, generally Cardinal IG's are not sold directly to contractors or homeowners, so curious where you are getting them from.

    To put it in perspective, Cardinal's 11 IG plants combined might produce 100,000 IG units a day for most of the largest window manufacturers in the US.

    Since Cardinal manufacture's their own glass as well as applies their own coatings, they have complete control of the process from sand to finished IG units. To deal with that volume level, there are quality checks in place throughout the process from start to finish.

    Do your IG units include laminated glass? If not, then the reference for how laminated glass is labeled will not apply to your units. Totally different requirements.

    Each IG will have a tag applied at the IG factory on the glass surface that will have all the statistical information pertaining to your IG. The tag is applied at the beginning of the process and has a bar code that is read by automated equipment to verify that it's being made correctly.

    edit.....I typed all this before i saw your recent post that the IG's have arrived, but I will leave as originally posted.

  6. [email protected] | | #8

    You have single strength clear annealed glass (2.2mm) with an 8mm airspace and LoE-270 on glass surface 2. The IGU's were manufactured at Cardinal's Spring Green WI IG plant four days ago using the Endur spacer system, which is the best IG system you can get. The IG's were sold through a distributor in Elgin IL

    The 475192 is the unit ID code for that particular IG. With that number Cardinal could tell you to the second where that unit was at anytime during the manufacturing process. They could even tell you (but wouldn't of course) the name of every person at each step of the manufacturing process.

    The rest in internal routing and set up information.

    You can trust the tag to be correct. If it wasn't the IG would not have made it through the process.

  7. gordy_b | | #9

    The installer/contractor said he ordered them directly from Cardinal, not sure why the sticker and paperwork that arrived with the IGUs says "Casco Industries."

    I did not specify laminated glass.

    By "tag" you mean the sticker not the etching as I see no reference to "8" (as in 8 mm) in the etching??? There is an "8" on the sticker in what I'm thinking is the "stack up" - 2 2 (=2.2 mm) CL (clear) A (annealed) E270 8 0 (8 mm gap) FED (no idea) 2 2 CL A (the room-side 2.2 clear annealed sheet).

    Now let's say, ah, hypothetically, I took some of someone's advice when ordering these but not all of it and took a chance on i89 for the room-side surface. And that I ordered Neat+ to help keep the outside surface clean. And that I ordered an Argon fill. Cardinal seems like a pretty precise operation - why would these two coatings and the Argon fill not be listed either on the sticker or the etching in the glass???

  8. [email protected] | | #10

    Cardinal did have a program a few years ago that they would sell IG's through a few distributors. I thought that program had been discontinued, but apparently some plants are still running it.

    The etching on your glass is unique and not generally used on IG's intended for window companies. It's included on your IG's for ID and warranty I would guess.

    I don't remember what FED means either, but I think it ID's the spacer and argon fill, but don't quote me on that. I will call them in the morning and find out what it means.

    If you had ordered I89 and NEAT that should be indicated on the label. Are you sure your contractor actually ordered them? Or is it possible that they were not available on IG's through a distributor? I think you might end up regretting I89, if you have it. Unfortunately not a great idea in your situation. NEAT is okay though if that widow gets a good amount of direct sunlight.

    Argon might not be indicated (depending on FED) because its automatic. Unlike mom and pop operations, Cardinal adds the argon as part of the IG assembly process, not as an afterthought.

    1. gordy_b | | #11

      Oberon, thanks for considering how one verifies invisible products like coatings and gas. POSSIBLE FURTHER ORDER->PRODUCT MISMATCH...

      (First, I am taking a chance on the i89. But, the damage with the old IGUs to the frame is minimal so I'm betting between argon, a wider gap, and a warm spacer (and increasingly warm temps around Chicago) these will balance the i89 at least enough to not make condensation worse than it's been the last 70 years.) On to the possible mismatch...

      This is literally a copy of the specs I e-mailed my window contractor who said they'd pass it along to Cardinal...

      Neat+ (surface 1 = exterior)
      2.2 mm glass
      LoE2-270 (surface 2)
      3/8" (= 9.8 mm) gap/Endur IG spacer (please communicate this to Cardinal)
      Argon fill
      2.2 mm glass
      LoE-i89 (surface 4 = interior)

      The 270, 2.2 mm glass, Endur spacer, and i89 and the Neat are on the paperwork that came with the IGUs (see attached paperwork). So they were at least in the order system.

      You wrote "At 1/2" there are two possibilities - 2.2mm glass with 3/8" airspace or 3.0mm glass with 1/4" air space. 3.0mm is also called double strength glass. Given the option, the 3/8" air space is better despite using single strength glass." So, I had specified 2.2 mm glass and the 3/8" Endur spacer (what Cardinal calls 9.8 mm). You think the sticker means there is an 8 mm gap (are you sure???), and this does match up with my measurement showing the total depth of the new IGUs to be a tad less than 1/2" (with the 3/8" gap they should have been ~1/64" over and I'm measuring with a metal ruler divided in 32cds so I can tell the diff between over and under 1/2").

      The "8.0" in the stack up (2 2 CL A E270 8 0 FED 2 2 CL A) must mean I received a 5/16" (8 mm gap) NOT the 3/8" (9.7 mm) gap I ordered, right???

      1. [email protected] | | #12

        I did say 8mm GAP when I should have said 8mm SPACER. My bad because the terms are often used interchangeably in informal professional discussions and it never even occurred to me that using gap versus spacer mattered in this case, but it did as it turned out.

        So, to be more precise, the spacer is bonded to the glass with .8mm (+/- .1mm tolerance as I recall) PIB on both sides of the space for an overall GAP width 1.6mm greater than the width of the spacer alone.
        8mm + 1.6mm = 9.6mm or 3/8" overall.
        Since you requested a 3/8" or 9.7mm GAP, that's what Cardinal manufactured using a 8mm spacer plus the PIB to give you the GAP that you requested.

        FED....F is a spacer designation (B would mean black spacer for example), ED means Endure.
        And argon isn't on the tag because unless otherwise specified, argon is the standard, not an option.

  9. gordy_b | | #13

    Hmmm... I'm going to have to think about the total depth a bit more. Being a newb I might have conflated spacer and gap.

    I'm glad to know the Endur spacer specified is in the units.

    I'll be looking more into how to determine the makeup of IGUs after the guests that are here for the weekend leave.

    Thanks Oberon.

    1. mr_reference_Hugh | | #14

      Did you call the company? Just curious.

      1. [email protected] | | #16

        Cardinal might manufacture upwards of 100,000 of these a day at 11 different manufacturing plants. They were ordered and sold through a distributor.
        Who would you call and what would you ask them?

    2. [email protected] | | #17

      You're welcome.
      What's your concern about the depth? Are you worried they may not fit?
      The make up of the IGU's is exactly what is stated on the tag/label.

  10. Deleted | | #15


  11. mr_reference_Hugh | | #18

    Spring Green, WI
    Cardinal IG Company
    1011 E. Madison Street
    Spring Green, WI 53588

    Suggested questions are the ones you posted.

    How can I check those specs were actually followed?
    As far as checking the glass thickness I believe I read it will be laser inscribed somewhere – does that sound correct?
    Will the low-e and “self-clean” coatings applied be laser inscribed?
    If not, is there any way to know the layers I ordered were applied?
    Add any questions that came up since:
    How does one find the documents to learn how to read the labels, markings, codes?

    To be clear, no pun intended, I am simply suggesting that you try. I don't know how helpful they will be. To me it would be the first thing I would try.

    I tried calling tonight at 2:45 AM but there was no answer for any automated system.

    1. [email protected] | | #19

      How do you know the IG's came from Spring Green, other than I mentioned it earlier? If you are going by what I said, how do you know I am right?

      "As far as checking the glass thickness I believe I read it will be laser inscribed somewhere – does that sound correct?"

      No, glass thickness is not normally inscribed on the glass. There might be an occasional exception if requested, but probably not likely with a small one-out order or even a large order without a very good reason.

      "Will the low-e and “self-clean” coatings applied be laser inscribed?"

      LoE 270 is listed in the logo on the glass. This is not typical when IG's are going to major window manufacturers , but might be standard (?) for IG's going to distributors. Clearly (also no pun intended, well maybe a little) NEAT is not included in the logo, but is on the label. Argon is standard, so I wouldn't expect to see it listed anywhere including the label.

      "If not, is there any way to know the layers I ordered were applied?"

      Yes, if it says so in the logo and/or on the label, then you have EXACTLY what it says.

      To see where the coating is located, hold a flame or even your phone light next to the glass when it's dark and look for reflection. You will see 4 flames or lights reflected in the glass corresponding to the four glass surfaces in the IGU. Three of the reflections will be close to the color of the flame or light, one will be different. The one that's different has the LoE coating.

      "How does one find the documents to learn how to read the labels, markings, codes?"

      If you are asking about the information on the printed label, there are no documents outside of Cardinal that are going to tell you what it all means. What other information do you want to know about what's on the label?

      And speaking of the label, the label is computer generated from the original order. As I mentioned previously the 475192 is the unit ID for that particular IG. The barcode below the UID on the label contains everything there is to know about that IG unit.

      The label is applied to the glass during the process and it is read by the computer to verify that the materials are correct as the unit is assembled. There are multiple automatic and manual checks along the way during automated assembly process to ensure that it is correct...If the label says that the IG has 2.2 glass, 270 coating, 8mm spacer, then that's what it has.

      1. mr_reference_Hugh | | #20

        Oh. Ok. My mistake. I should not have suggested calling. Please accept my apologies.

  12. [email protected] | | #21

    No, sorry that was my bad, I was trying to emphasize that it simply wasn't necessary to follow up on the accuracy of the build and I got carried away.

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