bathroom wall

when i nstall my 1/2 inch durock what spacing shall i leave when i connect the back wall to side walls between durock , and once i get the spacing right do i caulk in gap or use grout

when i install back wall durock do i stop it on top of tub flange or let it overlap flange about how much?

 

You can set the board on top of the flange. Let the plastic vapor retarder behind the cement board lap just over the top of the flange. Leave a 1/8" gap in the corners and fill with silicon caulk, let dry, then tape all seams and corners with mesh tape embedded in modified thinset.
When you set your tile leave a 1/8" gap in the corners and fill with caulk in the same color as the grout. Along the bottom leave a 1/8" gap between bottom row of tile and shower pan, fill with same caulk.

 

Tileguybob: If I understood that last response, the Durarock rests on the nailing flange. Then the bottom of the first row of tile is unsupported by the Durarock but is set up against the flange down to 1/8" above the shower pan itself. Did I understand this correctly? Thanks.

 

Most flanges are about 1 to 2" high. If the cement board comes down to the top of the flange most of your tile would be cemented to the board with the remainder of the tile overhanging the flange. If you are using a small tile like a mosaic then go to Plan B which is bring the cement board down over the flange and have it stop about 3/8" above the base, Then bring the small tile down and stop 1/8" above the base. The problem with bringing the cement board over the flange is that you may see the bottom of the board "curl" out due to the thickness of the flange. Best way, usually, to get around that problem is to put 1/4" furring strips up on the studs so the backside of the cement board is now flush to the front of the flange, therefore eliminating the curl

 

Do you ever notch the studs and recess the pan rather than fir the studs?