Framing Glass Block Window In Shower?

[Askel]

I'm building a wall between between a tub and walk in shower. Both sides of the wall will be covered in durock and tile.  I have a 23"x48" glass block window (just glass blocks stuck together, no existing framing) I'm going to put in this wall.  Wall isn't built yet, so working with a blank slate here. 

Any recommendations on how best to do this? 

Thinking of doing the framing in treated lumber then maybe slathering everything in something like hydroban and then locking the window in place with some kind of vinyl 3/4 round and then tiling up to the edge of that.  Then of course giving everything a good caulking after finishing.   

But I've never seen this done in person and googling it is finding lots of other folks in the same position asking the same questions.  Any pointers appreciated!

[sonofsven]

It's been a long time since I built a glass block window.
I wouldn't bother with PT in the wall, since moisture shouldn't be getting in the wall cavity.
If you're talking about using PT as a jamb and building the block wall on it, I wouldn't do that, either. PT doesn't look good, and I wouldn't want any exposed wood on the wet shower side.
I would build a waterproof wall out of something like Wedi, it's a foam board with like a fiberglass skin that you waterproof with their caulk; I prefer it to Schluter and the cement based backer boards.
So frame the wall and skin it with 1/2" Wedi, and use rips of the 1/2" Wedi to build jambs, waterproof it, then install the glass block and tile up and over the jambs to the block.
You could also use metal trims to butt into the glass block and overhang the jambs enough to make a stopping point for the wall tile, like a picture frame around the block, but the trims are so thin they won't cover any gaps between the glass block and the Wedi jambs as well. Maybe make a smaller rip of Wedi at the top of the blocks?
The issue is that you'd want a little wriggle room to get the glass blocks into place in the frame, and you also want consistent reveals around the whole thing for aesthetics.
I hope this makes sense.
Also, I'm pretty sure Wedi was the first product to market, but now there are competitors with similar products; basically a foam based backer board and shower pan system.

[Askel]

Thanks @sonofsven ! I was hoping you'd chime in. Good advice, I appreciate it. 

[lthenderson]

I've never built a glass window but if I did, I would do it the was sonofsven described above. Probably the only thing I would do differently, which depends greatly on your tile of choice, it to get some bull nosed tiles and use that to tile a frame around the glass block window once set in place to picture frame it and then butt your other field tile up to that. When I built my shower with a built in shower caddy, I did the same thing and used subway style bullnosed tile to frame around the inset portion and then did larger format horizontal tile for the field. Most shower tiles offer bullnosed versions of their tile for the transition to the rest of your untiled bathroom walls to avoid sharp edges.