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Community and Q&A

Picture Windows Inside Shower??

PowderSki | Posted in General Questions on

In a corner bathroom, I’m planning for a wet room in the corner, with both a shower and a freestanding tub inside. Inside the wet room I’d like to install two picture windows meeting at the corner.

I’d like to avoid wood windows for such a wet and humid place. Would Andersen 100 series Fibrex windows work well for this? Or should I just use basic vinyl windows?

I’m in Vermont, so condensation due to cold glass is a concern. Elsewhere in the house the windows will have Andersen’s HeatLock coating, but perhaps these windows shouldn’t have HeatLock, since it would result in a colder inner pane and more condensation inside, right?

I’d hate to go to the trouble to install these just to have them completely fog up anytime someone uses the shower, so how do I avoid that? (Triple pane would be nice, but not sure if they are available in Fibrex or vinyl, plus the cost might be prohibitive.)

Thanks for any advice!

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  1. Mark_Nagel | | #1

    I'd recommend checking out code first before leaping.

    Section 308.4.5 seems applicable to your case.

  2. Expert Member
    Michael Maines | | #2

    Powderski, I always try to avoid having windows in showers but have done it several times anyway. Any fixed window with a PVC or fiberglass frame should work. As Mark notes, it has to have safety glazing, and you also need to detail the interior to shed water just as you would the exterior. On a few occasions I have specified a separate piece of "frosted" (acid etched) safety glass at the interior.

  3. Expert Member


    As Michaels said, any PVC of fiberglass window should work. The problem is that windows are specifically designed to resist water intrusion from the exterior, not the inside, so some profiles of either type may not be appropriate. I'm not sure beyond looking at them how you could find out. I doubt any manufacturer will be willing to say their product will work in that situation.

    Much more important than the window is how the surround is detailed. That's where the potential for water damage is.

    No matter what window or glazing you choose, I don't think there is any hope it won't fog up during use. Glass shower walls do, and they have a much smaller DeltaT in the same humid conditions.

    1. Expert Member
      Michael Maines | | #4

      Malcolm, good points. There is an anti-fog coating you can use on shower glass or ski goggles; maybe that would work for the windows. Or a heat source blowing across the window, but that would get complicated.

  4. PowderSki | | #5

    Maybe Rain-X?

    Mark, thanks for reminding me about getting tempered glass. That's a good point.

    1. Expert Member
      MALCOLM TAYLOR | | #6


      I always try and give the wind0w supplier a full set of plans, not just the window schedule. There are a quite a few places building codes can require tempered glass. Entries, windows with low sill heights, stair landings, wet areas, close to lot lines, etc. Putting the onus on the supplier to ensure the glazing meet code means any mistake is on them, not you.

  5. onslow | | #7


    Anti fog wipe on coatings wipe off eventually. Making them 100% even is also problematic.

    I am looking at solving a similar problem for a wet tub/shower room though perhaps not quite as full frontal. The attached pdf from Thermique is what you are looking for I believe. Haven't gotten to call them yet.

    The tree hugger link gives another perspective on your plans. If you have a large solar array, I guess you could get a pass.
    As a practical matter, I can't imagine the stresses being placed on a seal that has 10F on one pane and 90+F on the other. Also, the non-heated performance U values might make such a window a very poor performer. Leaving it on all winter might be costly.

    Some of the following links are for overseas companies, but perhaps there are US vendors. Maybe the one in Chicago is the best answer.

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