I have had a window in my shower for 5 years and have not had a mole or mildew problem at all.

I don't love a window in a shower. What about glass block?

Does glass block get mildewy? Is it costly? The window doesn't need to open. Thanks.

I have a window in my shower for 15 years and have not had a problem with it. I do wipe it down after using the shower.

No, I had one in my previous home and when it would sweat the bottom would stay wet.

Why do you need a window in a shower? It makes no sense, and I agree it's just a good place for mold and mildew to grow. Listen to your architect--that's what you're paying him for!

Why not? It will let in natural light and look good. In one of the bathrooms I designed, I made sure to cap the window with marble slabs and seal it well to avoid water penetration.

The other issue - unless you have absolute, total, and forever privacy, is a window covering. I think this is more of an issue at night when you feel like people really can see in and you can't see out.

It can certainly be a nice addition to have a window in the shower for the extra natural light and ventilation but as said above seal the substrate very well - really it should be your primary barrier to moisture. Once sealed by an experienced tile setter then install a solid slab (not more tile) and slope it generously - not the minimum often used. Make sure to seal between the tile and window with either 100% silicone or another sealant per your tile setter - not your standard caulk.

https://www.houzz.com/photos/vertical-subway-tile-contemporary-bathroom-seattle-phvw-vp~20164591

And sometimes you buy a home and that is where the window is.

You could consider a frosted or cast window so you're getting the natural light but also still obtaining your desired level of privacy.

We advise against it as well for the reasons that have already been stated. While it can be made to last a long time it is still a concern, in some cases the Bathroom can be rearranged to allow a window (depends on where the door is really) if it is really important to the client. Other alternatives would be to add a Skylight or Solatube to get some natural light without the downsides of a window in the shower.

Good luck with your project!

We have a window in our shower, it is up high and requires no covering. It has been in our home 13 years and no problems at all. I do like the light it lets in. We do wipe our shower and window area down after every shower, well almost every shower, lol and no problems at all with mildew.