Exterior Window Used in Shower?

"Good afternoon,
I am in the process of designing/building my home and have a question. The exterior wall will be a curtain glass system in the master bath (for the view). At this point, I've planned for the shower to be on this exterior wall but have the following concerns:

1. will it be too cold (in the winter, home is facing north-west and is on a large river, -20 degrees). I understand if the wind was to permeate, it would be at the joint from window to frame but there is still less R-value in a window than solid exterior wall.

2. Will there be condensation issues? How to properly finish if the window is floor to ceiling?

The sales person at the window company said it would be no problem at all but I really would like a second opinion from a professional!

Your input would be VERY appreciated!
Thank you,


I love the idea of lots of glass in the shower, but the issues that you have raised need to be considered.

You may have a draft situation depending on the window type, size and manufacturer. However, if the glass is fixed (non-operable) and care is taken when sealing the window to the wall, drafts shouldn't be a problem. I suggest using a window with an integral flashing fin that can be sealed to the wall sheathing.

In a cold climate, there will definitely be condensation on the inside of the window. You won't be able to see outside clearly. This may be a good thing because people outside won't be able to see inside clearly either. Condensation also can create a maintenance problem when interior finishes are often wet.

I would consider installing an interior shower curtain over the glass. The curtain can be open when the shower is not in use or when it's warm outside.

Good luck with your project,
David Moore, AIA
Original Home Plans

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