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Fiberglass window manufacturer comparisons

Redrockcanyon5000 | Posted in Energy Efficiency and Durability on

Has anyone used Duxton Fiberglass windows lately?

I’m also considering Inline, Accurate Dorwin, and a smaller shop called Silex. Accurate Dorwin and Silex use PPG IGU’s. Inline and Duxton use Cardinal IGU’s. I’m also considering…

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  1. oberon476 | | #1


    Per the IGU, Cardinal makes their own from manufacturing the glass, to applying LoE coatings, to the final IGU. They offer a 20 year non-prorated warranty to the window manufacturer against seal failure.

    PPG (recently sold to Vitro) does not make their own IGU's, but they do manufacture the Intercept and supercept spacer systems which are used by window manufacturers and some smaller IGU manufacturers to build their own IGU's. Warranties for Intercept and Supercept vary by window/IGU manufacturer. Quality of the IGU varies widely between manufacturers.

    Cardinal's two spacer's (XL and Endur) are stainless steel while Intercept is tin-plated steel and Supercept is stainless.

    Energy performance and field-life, the stainless spacers significantly outperform the tin-plated spacer.

    If you are looking for triple-pane windows (which is likely the case based on your window company choices above), choice of spacer per energy performance becomes less important, but longevity may be more important because you now have two air spaces to consider and not just one with a dual pane.

    If I were you I would be asking myself - How do the overall window performance numbers compare between the companies? What about service and warranty? What is to like and not like between the the four manufacturers and their products?

  2. Redrockcanyon5000 | | #2


    Very good information regarding the spacers .Finding a window manufacturer that uses Cardinal IGUs has been challenging.

    Many window manufacturers are outsourcing the IGUs to smaller shops or are doing it in house.They offer "Cardinal Glass" but they are not genuine Cardinal Glass IGUs.

  3. GBA Editor
    Martin Holladay | | #3

    Duxton Windows in Winnipeg, Manitoba makes windows with pultruded fiberglass frames. As far as I know, all of their IGUs are manufactured by Cardinal. They are knowledgeable about triple glazing options.

    U.S. customers can take advantage of the fact that there is a favorable exchange rate now for the Canadian dollar -- favorable, that is, for Americans. (Canadians who purchase American goods aren't so lucky.)

    -- Martin Holladay

  4. ethant | | #4

    Duxton seems to service only some areas. Here in NY I was referred by Duxton to Inline.

    1. Phimnoi | | #5

      While on the subject of triple pane lowE and stainless spacers where does Fibertec, Inline, Silex or Pella fit into this discussion. I about to purchase 12 windows with pultruded fiberglass frames for Canadian climat zone 3, any advice would be appreciated...

      1. Expert Member
        BILL WICHERS | | #6

        Fibertec is expensive. I’m not sure they’re still in operation, either (check this though — there were two manufacturers with similar names and only one ceased operations).

        In-line is friendly and has a showroom almost across the street from Pearson airport outside Toronto. If that’s close to you it may be worth visiting them.

        Duxton is out of Alberta if I’m remembering correctly. They have a good reputation.

        I’m unfamiliar with silex. Pella is a US manufacturer and did not offer “full thickness” 1-3/8” triple pane IGUs as an option the last time I checked. If you want triple pane windows for thermal performance, you really want to go with the 1-3/8” thickness since it makes a BIG difference over the thinner compromise IGUs.


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