It adds more ventilation, which is always good in a WC.

i was thinking that but then wonder what type of window.. there is not much room on the back wall

We pulled it off the plans on ours and certainly don't miss it. We have a switch for the whole house air vent in there if you need more ventilation. I also prefer more privacy w/o the window.

We have one in both, side wall for both. In the master it's a square window up high. In the guest bathroom it's a regular double-hung set at the same height as the other windows. It is set forward of the toilet so the person isn't sitting right next to the window.

There is no window in our master bath wc. It is also quite small. I find it claustrophobic. I also concluded that my husband left the door open most of time because it feels confined. I am thinking of changing the door to the wc to glass (duly frosted) or even putting in a transom to get in some natural light. I suspect that if the wc had a window, we wouldn't have this problem.

Our toilet area is 3 x 5 with a pocket door (that is never used). There is a fully functioning window in there.. 28 x 48ish and we open it all the time.

When we remodel, we are losing the door, 1/2 of a wall, and installing a new window exactly the same size. There is another window in the master bath, they both face east.

We LOVE the natural light and when the master windows are open too (those face west), the breeze is heavenly. It helps that we have a nice view and privacy isn't really an issue.

The entire room would be a lot darker without it... couldn't really imagine not having that window!

I REALLY couldn't imagine having a closed room with no window.