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Community and Q&A

Air Sealing Used Windows – Casement vs Double Hung

mikeysp | Posted in General Questions on

Hi. I am in Zone 4a and am building a house on the cheap. 

I have acquired two sets of windows and want to know which I should use?

I presume the older wood casements as it seems they would be easiest to achieve an airtight seal compared to the double hung windows.

I like the vinyl windows because they can look brand new with a wash, but the air sealing is of great concern.

wood casement windows from 1990-ish, double pane, casement windows that open with a hand-crank.

vinyl replacement windows from 2000-ish, double pane, full double hung, tilt out.

The wood windows have a little mold from sitting in storage, but I will treat and paint them before install. 

Thank you for your advice.

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  1. Expert Member
    NICK KEENAN | | #1

    There's so much variation in windows it's impossible to know. I'm trying to think if there's a way of testing them empirically.

  2. mikeysp | | #2

    Thank you. If I can't figure it out, I will just use the casements on the house, since I am confident I can get good air sealing results.

  3. woobagoobaa | | #3

    All other details being equal, it is my understanding that casement windows generally offer better air seal than double hungs.

  4. Expert Member
    Michael Maines | | #4

    Mike, 20 year old vinyl windows are likely at the end of their life span, unless they have been in storage. The vinyl gets brittle with UV exposure, the glazing bead works loose (unless it is high-quality and installed with a bead in a groove), and if they are tilt-outs, the jamb liner probably needs to be replaced. If it's a spring mechanism, that might need to be replaced. But depending on the application, they may still have some life in them. They will not be as airtight as a casement can be, but the difference is not always huge.

    With the casements, you'll probably want to replace the gasket(s) and hardware. Wood casements usually fail at the bottom sash rail, so just make sure that is in good condition before putting effort into them. It needs to be structurally sound, not just patch-and-paintable.

  5. Expert Member
    Dana Dorsett | | #5

    >"I presume the older wood casements as it seems they would be easiest to achieve an airtight seal compared to the double hung windows."

    That's correct- much easier to make reliably air tight. Wood sashes are also more stable with temperature than vinyl too.

    Are there any low-E on either set of windows?

    If you 're not sure, look at the reflections of a candle, lighter, or LED flashlight. There should be four reflections, one for each surface. If there is a low-E coating one of the reflections will be a noticeably different color. Surfaces #2 or #3 (the surfaces facing one another inside the sealed glass unit) are the most likely to be coated.

  6. user-2310254 | | #6

    Whichever way you go, I would try to install the windows so as to minimize removal and replacement. I'd also follow best practices to prepare the window openings. Hammer and Hand has a good detail for that:

  7. oberon476 | | #7

    There is a huge difference in quality, performance, and longevity between high-end and low-end in both wood and vinyl windows.

    First question should be, if you can identify them, who originally manufactured the windows? If there is no way to identify them then that may be a red flag in itself.

    I get that you are building on the cheap, but cheap can become expensive if a year down the road they are all failing. If they were higher-quality from the start then there is a much better chance that they have a good bit of usable life left in them. And while I am not suggesting they aren't worth using, I am suggesting that one other consideration to take into account besides material and style is original manufacturing quality.

    Initial quality matters and if one batch originally came off-the-shelf from a big box store then, even if they were free, there may be a better than even chance that you are getting exactly what you paid for. Whereas if they came from a better supplier (or line, some lines may be good and some bad even from the same company) then you should have less worry about long term performance.

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