Hello, I too have joined the ranks and am currently remodeling my bathroom. I am using 1/2" Hardibacker on the walls of my surround for the tub/shower after which I will tile. For now, I have read several threads on how to handle the seams on the Hardibacker and they all make sense. However, I have not seen anything on how the Hardibacker should be joined to drywall, in particular to the ceiling. At this joint, where backerboard meets Dryall, do I use the same Fiber tape and thinset mortar seaming method as if the seam were a Hardi meeting Hardi? Advice would be appreciated!
Using the same tape, thinset on the Hardi, drywall compound on the drywall. Thinset can be used on the drywall where they both meet if the thinset will be covered by the tile. Compound can also be used on the Hardi (to some extent) if it is outside the shower area. If you did not use a vapor barrier before the Hardi went on, then i would suggest a waterproofing such as Redgard.