bathroomcement-boarddrywallfinishing
Trying to figure this out.
I am going to be using Hardibacker for wet areas around the tub-shower above the acrylic tub/shower surround, and drywall for the rest of the room.
There will be no tile.
The whole room will be painted.
What should I use for the gaps where the drywall and the Hardibacker meet?
Thank you for your time.
A usual method is to go down the edge of the wall with a surface bullnose, showing a "knife edge" at the corner. This means the tile rolls down to meet the corner.
Another method, if your bullnose has finished bottoms, is to overlap the edge and go "around the corner", having the bullnose round into the outside wall (the wall that has the striped wallpaper) The bullnose will hide the tile edge, putting that grout line facing the side of the entrance.
This photo shows both methods: the left with a flat-on-wall knife edge and the right shows a wrap-around-the corner
You can use the edge profile pictured, in place of surface bullnose. You would adjust your tile to end short of the corner (equal to the edge thickness of the profile.
In all cases, grout would be filled into the corner/wall junction.
I had a similar situation where the backer board extended a few inches past my planned tiling edge in my shower. After I had finished with the tile, I taped the joint and applied joint compound over the backer board and it seems great. It's been three years and there is no cracking or any problem with it. That's not exactly an answer but I hope it helps you decide.
Best Answer
If you are going to paint, the seams between the drywall and the hardibacker will need to be mudded and taped like any other wallboard seam or the joint will be visible and ugly. it will probably be hyper-visible actually, if you use glossy paint (as you should in moist areas).
I think you'll be fine with standard mud/tape, it's not a wet location, just moist if it is indeed above the splash zone (if it's not above the splash zone, you should use an alternate surface treatment instead of simply hardibacker). A good prime and gloss paint should protect the drywall, mud joint, and hardibacker.