Windows: Marvin Fiberglass vs. Okna uPVC?

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Windows: Marvin Fiberglass vs. Okna uPVC?

#1 Post by Jax12 »

In our house, the original metal windows from the early 1970s still exist. As far as the vibe we got from them, we've limited it down to our top two vendors, and they're about the same price.

One provides fibreglass windows from Marvin Essential or Marvin Infinity. The other vendor offers Okna 500, an uPVC substance.

So which choice is best when comparing windows side by side without considering price? Would one have less colour fading if it had a black outside and a white interior? Will one be more effective? Everyone agrees that fibreglass should cost 30% more; yet, even if this is the case, I'm leaning toward fibreglass because it seems to offer a better value.

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Last edited by Jax12 on Tue Aug 16, 2022 3:24 am, edited 1 time in total.

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Re: Windows: Marvin Fiberglass vs. Okna uPVC?

#2 Post by TheWindowNerd »

That is a tough call.
I am a dealer for both.
From what I see the black finish on the Marvin is better, but I have had no call backs on the Okna black.
The Okna is more energy efficient, less drafts. I use their 600 or 800 in DH.
The other consideration is visible glass comparison. I don't want to take all the work away from your vendors, let them help with that one.
If it were my house I would go with the Okna.


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Re: Windows: Marvin Fiberglass vs. Okna uPVC?

#3 Post by HomeSealed »

You are comparing apples and hamburgers. Both are good, both can be the better choice, but it really depends on the details and what you value. Like TWN, I've sold and installed both. If you are concerned about the performance of the window, the Okna is superior in EVERY measurable area thermally AND structurally despite what the Marvin brochures will imply, and a much better warranty to boot. For most people, as long as you find the appearance of the vinyl window acceptable, this makes it a very easy choice.

With that said, the Marvin window are well built and have some of their own selling points. While I'd be careful not to put too much weight on this, the black exterior on the Marvin is probably slightly more durable as TWN alluded to. You also have some options for painting or staining the interior on that window, which is not available on the vinyl windows. When a wood interior is chosen, there's definitely a richness in that product that can't be matched by vinyl, however given that you said white interiors, again I'm not sure how relevant that is in your decision. Most folks I know would say that a whole Okna 500 looks and feels nicer than a Marvin Essentials, however equal or slightly less so compared to the Infinity. Lastly, there's the Marvin brand that is of some value as well, more to some than others.

Ultimately, based on the information that you've provided about your project I'd say that the Okna is a better option with out regard to price.

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Re: Windows: Marvin Fiberglass vs. Okna uPVC?

#4 Post by Windows on Washington »

Honestly, to my surprise, we've had ZERO issues with the darker painted windows from Okna. Never really thought that the paint would hold up this well, when first released, but we have jobs that are approaching 17 years old that look, basically, brand new.

Price and performance = Okna

Most Steel Window look = Marvin Essentials all Ultrex

Most Air Leakage for a window that feels like its open when its actually shut = Marvin Infinity (the Infinity refers to the continues breeze).

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