I'm rebuilding my shower and using HardiBacker (1/2" thickness) in that space. I've then got normal green-board drywall that I'll be transitioning to. I figure that I'll tile up to the edge of the HardiBacker.
The real question here is whether I should seam the HardiBacker to the drywall using:
(A) normal tape and drywall mud
(B) paintable caulk
(C) something else or some other solution like tiling over the seam by an inch or so, etc.
I've seen some interesting answers online like (A) and (B), and I can see advantages to each - (A) would make for a pretty smooth surface transition while (B) would allow for a permanently flexible (since the two different materials should in theory expand and contract at different rates), waterproof transition that could be repaired if a crack were to form and could be covered with grouted caulk. So in short, does anyone have some thoughts or suggestions?
A few additional notes - I'm planning to over-engineer this shower by putting Schluter Kerdi liner over the HardiBacker as I like the idea of redundant waterproofing solutions, and I like the idea of using something like KSL1400 (a prebuilt shower pan with integrated liner and slope).