How do I patch my wall with tile along the seam?

Question

I just removed the top 6" of tile from my bathroom wall which is tiled from the floor to about 4 feet up. I just didn't like the pattern of tiles at the top. The tile seems to have been attached to the drywall with cement, not tile adhesive.

Removing the tile completely destroyed the drywall behind it, so I cut it out entirely & will now buy new drywall & replace this 6" strip that runs all around the bathroom.

Since the one edge of the drywall that I'm replacing is still covered by tile, I can't tape & join it properly. That edge is also not a clean edge, but crumbly. But I can't go any further because the tile I'm keeping is there.

My question is this: How can I make this repair strong if I can only tape one edge? Can I fill the crumbly edge with joint compound & hope to get a good bond between old & new drywall?

I do not plan to re-tile over the new section, but will put in a wood moulding with a ledge, so the whole repaired area will be hidden, but not by tile. There are studs every 16" in the area to be replaced - the new piece of drywall will definitely be securely attached to the studs & the drywall above, but nervous about the connection to the drywall below, as explained above.

Answer 1

As long as you have secure anchoring of the 6" strip of drywall to the studs behind, and since the strip is along the ceiling, strength is not a major concern here. Additionally, the primary reason for using joint compound is not for strength but to create a smooth work surface for finishing.

In applications where the drywall will be completely covered, such as with a hard paneling, installation can be finished with no mud/joint compound at all.

In your case, since it's in the bathroom, along the ceiling, as long as the strip is out of the splash zone of the shower I wouldn't bother with mud.

Now if your shower is unusual and the ceiling is in the splash zone, then waterproofing will be necessary and you should use cement board not drywall - but it sounds like drywall or plaster was already used, so replacing it with more drywall isn't a problem in this case. (Or, if it is, you have much bigger issues already with the bathroom that are outside of the scope of this specific question.)

Answer 2

It sounds as if the strip you have removed is about 42 inches off the floor and not in an area that receives regular contact with water. If this is the case, you have no problem with your proposed solution of covering the joint between the remaining tiles and the new drywall with molding.

The strength in the new drywall is in the mounting to the studs, not in any mud joint. In your case, the only reason to seal the joint between the old and new drywall is to avoid air and minor moisture infiltration (not serious water flow) between the room and the wall cavity.

Since the actual joint will be covered by a molding and a ledge, how you seal the join is of little concern. You could use drywall compound, one of the hardening spackles, or caulk. I would recommend the latter.

And after the molding and ledge are installed, I would also recommend putting a small bead of caulking between the top of the molding or ledge and the surface of the new drywall before painting. This will give you a clean connection and ensure a good seal.