I am installing a bathtub, without a shower, in the basement. I only need to tile about 2 feet up from the tub. I want to use cement board under the tile and above the cement board I want to put green board, since I will not be tiling over the green board. Does this sound like a good way to go? How do I finish the joint where the cement board meets the green board, with mud or a tile setting mortar?
I’m a homeowner who is a little handy so this may not be the best answer, but I did a similar job myself.
The one I did had the upper and side edge of the concrete board butting against drywall. On the side edge, the drywall ended about half way to the stud so the edge butting to the concete was hanging without support. I figured that would make any joint there too flexible, so I used ‘L’ shaped metal brackets to firm it up. In answer to your question, I found that making the joint in the middle of the last row of tiles covered it nicely. In other words, the tile covered the joint instead of using mud or adhesive. It’s been over a year now and is holding up fine.- It may not be the ‘right’ way but it worked.