Hi all:

Pretty soon I'll start putting up the concrete backer board for a tub
surround, with the rest of the bathroom covered with drywall. The
backer boards' edges aren't tapered and as I'll be hanging the sheet
rock horizontally the vertical joint between the drywall and backer
boards will be a straight butt joint.

I have two choices as to where I can place these joints:

1) There are studs 28" out from the tub's long wall where I can meet
the backer board and drywall. The vertical rails of the tub's sliding
glass doors can be positioned here, hiding the vertical seam up to the
top of the door, leaving only the couple of feet exposed to the
ceiling and needing to be taped a covered with joint compound.

2) About 5" further out from the tub are vertical 2 x 4's turned
sideways that I could also use as the landing point, but the butt seam
would be exposed from floor to ceiling, requiring I attempt to hide it
as best I could using tape and joint compound.

I do plan to run the tile out slightly past the tub itself.

Can I simply thinset the tile across the backer board/drywall butt
joint if I place the backer board/drywall joint on those studs at
28"? I'm a bit concerned that the drywall, even hidden under the tile
in this fashion, is too close to the tub and could suffer water damage
over time.

Anybody think one choice is better than the other and, if so, why?

Or, is there some other way I should go about this?


*If the walls are open you can put some extra studs anywhere you want to
make it work for you. I had one do-it-yourself customer who gutted his
bathroom and put hardibacker board everywhere except the ceiling. No
drywall.