Green board for bathroom and kitchen Ceilings

Hi, I am in the middle of redoing the bathroom of my first house. I have the tub installed and need to build an alcove wall. My initial thought was to make the entire alcove wall out of glass block - but then I figured I would need at least a row or 2 of tile so that I can integrate the tile flange on the tub with the wall for water-proofing purposes. So now my thought is to build the stud wall up about 6"-1' above the tile flange, and then continue from there with glass block to the ceiling. My issue is this: I'm thinking to do this right I would need to have the glass block flush with the face of the tile. The way I was thinking of constructing the wall would be to first build the stud wall, then furring strips over the studs down to the tile flange and install cement backer board & tile over that. Is it possible to have the glass block flush with the tile? It seems I would have to have the front of the glass block supported by the furring strip & cement board...which I doubt is a good idea. The wall is going to be pretty heavy and I would think it should rest flush on the top plate of the stud wall (not overhang). I attached a rough sketch of what I am planning (without the glass block for clarity). Any ideas/suggestions? [ATTACH]36872[/ATTACH] Thanks, Steve

I'm working on a Bathroom reno. Older 1950's Single story home with Plaster over Drywall lathe. I have removed the walls to stud and wanted to clarify and ask a couple questions. Roughly an 7X9 space with standard 8ft ceiling. 1 exterior wall with a window, which is to the right of the back of the Tub area sharing the same exterior wall. 1. Walls of Tub surround - I have used Roxul for the insulation of the interior and exterior wall of the tub area. I have also hung 6mil Poly on the exterior wall and for the Tub area. I further plan to use 1/2in Hardiboard for the tub surround under tile, and then greenboard for the rest of the wall area where the Haridie is not being used. a. Any issue with using Hardiboard over the poly for the tub surround? I have read posts both FOR and Against??? b. is Greenboard for the exterior wall, over the poly, fine? or what else to consider? c. remaining interior wall area will use the 1/2in GB 2. Plaster Ceiling - left this alone, however removed a decorative header which framed in the old tub area. Short of patching the removed header section, I have decided to just hang drywall right over the old plaster to essentially re-level the ceiling instead of patching the old plaster. a. Can I simply hang the 1/2in green board over the old plaster ceiling? I have read that GB is not recommended for ceilings. Is that an issue in this case of going over the old ceiling? or what other method should I consider? Regular drywall 1/2 in or 5/8in? Thanks for the help and advice/