I am in the process of remodeling a bathroom and need to put up backer board/Durock. The problem is that the sheetrock is 1/4 or 5/16", and the backer board is 1/2". The Durcok website said not to use 5/16" Durock for walls, only for underlayment. So what do I do with the 3/16" difference between cement board & sheetrock?

I'm confused. You're tiling over backer board and want to mate it up where it joins with existing drywall?

Use the 1/4 backer board, tile over it, and then go back and mud and caulk the area where they mate up. The tile will be higher than the drywall. I don't think you can make them flush, unless you just get lucky.

The product info specifically says not to use 1/4" backer on walls. I don't expect it to abut perfectly, but having it start out 1/4" higher will make the finished product much higher than the drywall. I don't see what the hard is in using 1/4" backer, but I don't want to get it all tiled and have it go FUBAR on me.

Are you putting in the drywall or mating existing? I would use 1/2" drywall, then you've just got the thickness of your thinset+tile, which you can caulk and make look fine.

I thought you could use 1/4" underlayment for tile surrounds. Maybe there's too much flex. I used 1/4" over existing subfloor.

The drywall is existing, and I really don't want to re-do the entire bathroom.

I did extensive drywall patchwork in my bathroom. I really think I'd have made less work for myself if I'd just ripped the whole room to studs and started fresh.

That’s not what I wanted to hear AC! But, it makes sense. I ultimately want to replace the vanity and all but don’t have the $$ to do so right now. If I’m going to have to take everything out though, I might as well.

Almost finished with a tub surround tile install in bathroom. Also gutted out most walls for the remodel. Definitely take out existing sheetrock before installing backerboard. Drywall is alot easier to work with/fix than the cement board. My two cents. By the way a shower tile install around the tub is a PITA!

put a 1/4 inch sheet of drywall over the existing drywall to make it flush?

If you are going to do that, I would say just rip out the old drywall and put in 1/2". You would still have to finish the corners and joints.

I was in the same boat a few weeks ago. I had ripped out the old tile and was having a new bathtub installed. After looking at all the patchwork I would have to do, I decided to rip out all the drywall and start from scratch. Right now I am in the middle of finishing the drywall, and it sucks. Hopefully it will turn out OK and I will be glad I replaced it.

True.

Half inch quarter round down the seam? Would be pretty close to flush with finished tile height probably. Or 3/4" if that would be closer.

Just a thought on tile installation depth.

I used 12x12 tiles and powder mix mortar installed with 1/2 inch trowel and the total depth from cement board to outside of tile after installation was 1/2 inch.

Good idea ice

Awesome!

This is not a high-end house by any means. This is my first home and is in the <$100k range.

If it were me, I would have no issue using the 5/16" durock. If you are worried about the patch over the transition between the durock/drywall not looking good, can you just bring the tile out far enough to overlap the existing drywall by an inch or two? Would that be possible?