How do I seal a bathroom window?


A bathroom was added decades after the house was built (104 years ago) and there is a full size window in what is now the shower. The moulding is thick and beautiful and in good shape-I have no desire to tear it out. (the house is brick, so there is that, too) Currently I have a shower curtain hanging over the window, which is not ideal.

Here is my thought-

1-put adhesive diffuser stuff on the window (so it's no longer clear, but light can still come in-that peel and stick stuff)

2- some kind of waterproof sealant on the frame and windowsill, and then

3-use a plastic window kit like the kind used to seal windows both indoor and out, in winter. (3M is the one that comes to mind)

Most important though-will these window kits completely seal the frame to keep 100% of moisture out?

2nd-what product is best for sealing the wood-should I look at marine products?

Thanks in advance. My hubby (who grew up in a family of contractors) said this is not a solution, but he has not offered anything different, and in the past has not shown any creativity when solving issues that are 'no-typical'. So I am not likely to believe it is an impossible situation.

  9 answers
  • I don't think the window seal kit will form a seal good enough to solve your problem. You can used etching cream on the glass so it is no longer transparent, but light will still come through. I'm leaning toward marine varnish for the wood - it works on boats!

  • Cynthia H Cynthia H on Jan 16, 2021

    Hi! I agree about sealing the wood. I wouldn't use a plastic or vinyl window kit. I could consider having another pane of glass or plexiglass made into a storm window insert. Then, I would seal around it with silicone caulk. What are you trying to accomplish, more privacy and/or keeping the room warmer? For privacy, the etched glass could be the insert. My daughter has a bathroom in a very old house, with a window like you are describing. We put a shower curtain that had been cut down to the right size on a tension rod and it gave the extra privacy needed. Good luck and stay safe!

    • See 1 previous
    • Cynthia H Cynthia H on Jan 18, 2021

      Glad to help! Please consider posting your solution!

  • William William on Jan 16, 2021

    Helmsman Marine urethane may seal the wood. But it would need to be recoated every so often. Transparent Contact paper on the glass.

  • Betsy Betsy on Jan 16, 2021

    Hi Christin: Nothing is impossible, just maybe improbable :) If hubby won't help, maybe he doesn't know what to do. I'd seal the frame with a water proof sealant. Is it raw wood? If so, Thompson's Waterseal is good. Homedepot has some really nice stuff to put over glass in nice patterns. Here's the site: As for sealers, Seal Once is good. It's for exterior wood decks, but should work on your window. Also, you might put on some clear caulking if you don't plan on opening the window.

    Good luck

    • See 1 previous
    • Betsy Betsy on Jan 17, 2021

      Great, happy to be of some help. You're right, where there's a will (I want to be in it!) there's a way.

  • on Jan 17, 2021

    Lots of wood trim in the outdoors get more moisture than a shower. Maybe an outdoor paint would be ok to use here? Or is your wood natural? In that case marine varnish.


    • Christin Harding Christin Harding on Jan 17, 2021

      It is natural (I'm not sure-did fake wood exist 100+ years ago? Maybe?) I am going to look into options from the marine world-thank you for responding!

  • Sharon Sharon on Jan 17, 2021

    The one in my old bathroom, I paint with marine epoxy paint every couple of years and use exterior caulk around the joints.. I do have a hand-held shower head that I kind keep away from the wall as much as possible. I also have had one of those resin shower kits put in on the bathtub surround about 6' up that was cut around the base of the window and caulked. My glass is some old rippled sandblasted glass I believe.

    • Christin Harding Christin Harding on Jan 17, 2021

      Thanks Sharon! It sounds like you have found the perfect combination! I'm trying to make this as simple as possible (so it actually gets done! haha!) and the walls surrounding it are tile. So no surround for me, but the hint to use exterior caulking is very useful. I can keep the shower head away from directly spraying on wall with the window, so that is helpful.

  • Mogie Mogie on Jan 17, 2021

    Rubber glazing seals have excellent weathering, wind and watertight resistance.

  • Lifestyles Homes Lifestyles Homes on Jan 17, 2021

    Having had a new anodized aluminum window custom made for in-shower use, the manufacturer and installer treated it was the outside of the window, on the inside.

    it came with flashed mounting flanges and drainage channels. Only aluminum or stainless steel could put up with that kind of daily water.,

    I would havea very large plexiglas or Lexan screen made for it, that slides on mini barn door hardware. Better than a shower curtain.

    Putting a film on the windows is easy.

  • Kathy Gunter Law Kathy Gunter Law on Jan 18, 2021

    You could add a storm window on the interior as an alternative to your plan.

    However, I think your plan would work by using Rabbitgoo or other brand cling adhesive (I did this in my bathroom in a similar situation but at the toilet) for step 1 then use marine varnish for step 2. However, I think storm windows would be your best bet on step 3.