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Fibertec vs. Inline Fiberglass Windows

p_550spyder | Posted in General Questions on

Hi there,

Hoping for some advice and input from people who have used or know people who have used Fibertec and Inline for their fiberglass windows. I’m currently looking to change my old windows and I’ve done some research on vinyl and fiberglass, mostly. I’m likely staying away from wood or aluminum windows. I live in Toronto, Ontario so we have great variance in temperature and climate seasonally. Leaning a bit toward fiberglass, but haven’t made my decision yet.
I’ve gotten quotes from both parties, Inline coming in a bit lower than Fibertec. I understand the “benefits” of Fiberglass vs Vinyl, such as less expansion and contraction during temperature changes, although I hear vinyl is better as an insulator. I’ve also been told that Fiberglass can last as long as 35-40+ years but I find it a bit hard to believe the windows will perform quite so well for that duration of time, that I question after a good 20 years whether you wouldn’t arguably see that the windows at that age, would be worth replacing. The Inline sales rep was telling me it’s not really worth investing in triple pane as the climate here doesn’t quite warrant the need and is more recommended for those who live in Northern parts of the region, nor would it pay off in energy savings cost till decades later. Fibertec sales rep was advocating the opposite, saying it’s worth the extra cost, especially if you plan to live in your home for more than 5+ years. Cost difference between double to triple is approx 15-18% higher.

My question is, what is the general thoughts on what either of the sales reps are trying to inform me or sell me on and how much truth can I put in what either are suggesting?
Does anyone have thoughts on their experience or known experiences with either company? Perhaps recently, say 5 years or so, the quality of their windows, performance, look, their service and honesty living up to their warranties, should i.e. the glass fail or frame issues develop. Inline states their warranty is 20 years on frame and glass, not including service installation. Not sure of Fibertec, need to consult with the sales rep again.
Any suggestions to go with other companies,? I quoted Pella months ago, they came in higher than Fibertec and I also quoted Marvin who was a bit more than Inline but a bit less than Fibertec.

One other note is Fibertec makes their own glass, while Inline purchases their glass. Not sure which of the two is better, Inline used to purchase from Cardinal but unsure if they continue to do so and whether Cardinal is considered the best in this category at this point in time.

Appreciate any advice that can be shared.

Thank you,

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  1. [email protected] | | #1

    Specific to glass, Fibertec offers both Pilkington Energy Advantage (hard coat LowE) coated glass as well as several different Cardinal coated glass options. Generally speaking Cardinal glass is the option on their more energy efficient products. Fibertec does manufacture their own IGU's using superspacer, whereas last that I recall Inline was using the Cardinal IG system in their windows. Disclaimer that was a few years ago so not sure if that is still true or not.

    In any case, by most measures the Cardinal IG system is considered to be the premier product in the residential market.

    Generically, vinyl frames have the best energy performance of any window frame material. Even low end vinyl can outperform other products when it's new, but you do not want low end vinyl under any circumstance. Some fiberglass producers add foam fill in their pultrusions to improve energy performance, but I think the jury is still out on how effective that really is.

    In your environmentclimate (assuming that you aren't far southern Ontario), I would say that triple pane is a more than reasonable upgrade and personally I would recommend it all day long.

  2. p_550spyder | | #2

    Thanks Greg for the reply. I don't believe Fibertec offers Cardinal IG system anymore, at least that isn't what the sales rep informed me of and doesn't appear to be listed on their website either.

    How would one differentiate low end vinyl to high end? The only example of more higher end vinyl window that I'm aware of is a mirocellular frames. There is a company called Nordik that I believe uses that technology. Other than that, I wouldn't really know, how to spot out a cheaper vinyl, outside of a major price difference perhaps.

    I'm pretty far South Ontario, being in Toronto. Not terribly far from NYC. It's definitely not the coldest place in the province but it can get cold in the winter. So given how far south I am, would you say double pane is fine enough?

    Thank you.

  3. [email protected] | | #3

    Fibertec doesn't use Cardinal IG units in their windows but they do use Cardinal glass. Cardinal does sell annealed, coated, tempered, and laminated glass to window manufacturers that don't use Cardinal IG's. So there is a lot of Cardinal glass used in windows that don't use Cardinal's IGU system.

    Consider that while Cardinal manufactures about one third of all IGU's used in North America, they also provide about 70% of all residential LowE coatings. From those numbers, clearly not all Cardinal coated glass is used in Cardinal IG units.

    Cost really can be an indicator of a high quality vinyl window vs a junk product, but it's not 100% by any means. Even pretty good energy performance values might not be the best indicator since even junk vinyl windows can have better than average U factor and SHGC. However looking at DP rating and Performance Grade might be better indicators since they speak to the structural aspects, including air and water resistance, of the window and not just whether or not they use high performance glass.

    There are over 1200 window companies in North America and the significant majority of those are very small to small local or regional vinyl window manufacturers. There are some really great regionals such as Innotech in western Canada, and some less than stellar nationals such as SilverLine in the US. If you could compare those products side-by-side you would really see and feel the difference. Look at warranties. You want at least 20 years on the glass and an absolute minimum of 10 years on all the other components. Anything less than that, move on.

    Reputation among window pro's can be an indicator, but one that you need to take with the proverbial grain of salt because of personal prejudices that might affect recommendations one way or the other.

    Where you live triple would be nice but not really necessary. If the cost upgrade is reasonable (whatever you feel is reasonable, there is no formula), I would go for the triple. The downside with triple is they can be dark, but depending on the coating(s) used, certain dual pane windows can be darker than triples.

    Canada really likes to use passive solar gain in energy calculations, so that can affect coatings used as well.

    1. p_550spyder | | #6

      Thanks for the really informative reply Greg. Understood now on the Cardinal glass and Fibertec. It is certainly a tough decision to make. One of my biggest fears is making the invest, and only to have a number of issues shortly down the road. It really can be a gamble but gathering as much information as possible, hopefully will help to make the best informed decision. Appreciate you jumping to share your thoughts. Hoping some folks will have something to share in terms of their experiences with both companies. Unfortunately there is a negative one I see below re: inline and being true to their warranty.

      1. [email protected] | | #10

        Two other fiberglass companies you might take a look at are Duxton near Winnipeg and Enerlux in Nebraska. I don't know much about either of them , so not an endorsement of either of them, but I have heard or seen positive reviews of both.

        Since you did look at Marvin and Pella, my preference would be Marvin for both product and service.

  4. jamesboris | | #4

    Fiberglass has a coefficient of expansion much closer to that of your window glass than vinyl does. This may make fiberglass frames less likely to leak over time as joints open just a touch (maybe letting out that Argon you paid for). Heavier-duty vinyl will do better than cheaper stuff simply because it's thicker. On the day of installation, triple pane vinyl windows will perform as well as anything. Over the course of 20 years, I wouldn't trust vinyl as much as a nicer fiberglass window (be aware that many manufacturers say "fiberglass" but it's a composite that doesn't perform the same). I think the money/energy savings in the long term favor fiberglass. Blower door tests and first-year energy bills aren't the best indicator of the durability of a house... a well-detailed polyethylene vapor barrier in Houston can get you to PassivHaus blower door tests, but it'll rot out your walls before too long too most likely. These realities are often ignored in the melee of chasing the best blower door test possible.

    1. p_550spyder | | #7

      Thanks James. I certainly do believe that Fiberglass if built well, installed properly, should definitely outlast vinyl and perform better over say a 20 year period. I do wonder how well though...enough to say the windows could last another 10-20 years as many Fiberglass companies claim? Perhaps and for those that have invested in them, hopefully so. Which potentially may include myself. I have heard of the composite frames at certain manufactures marketing it as Fiberglass, one example that comes to mind is Renewal By Anderson and their Fibrex window and apparently a very expensive window. I will make note of such for any other window places I consider quoting with. Thank you for your advice on that.

  5. efficient_builder | | #5

    I strongly advise against Inline. Personal experience: ~50% failure rate and cannot get them to honor their warranty- over a year in trying to resolve this and they are unresponsive. Excellent pre-sale, awful post-sale service. Read the reviews (search this forum as well) and you will find similar stories.

    1. p_550spyder | | #8

      Efficient Builder that is really disappointing to hear you've had such issues with your windows and terrible service from Inline in response to living up to their warranty. This is exactly what I fear. I'm not sure if Fibertec will be better living up to their warranties or not. They both do have some negative feed back from what I've come across but I have found less info on Fibertec than Inline, suspecting Inline is larger and more well known between the two. Both certainly have a great looking window, I do think Inline might have a nicer look, cleaner lines and more modern overall and they are coming in at better price, just not sure if they have a higher rate of issues developing over time, with a poorer score when it comes to standing true to their warranty.

      1. p_550spyder | | #9

        Best of luck with your situation. I do hope they finally get back to you and provide you with the service you deserve and have paid for.

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