I did not take my time removing the tile backsplash in my son’s kitchen. I hacked the tile off with a pry bar and hammer. Directions after the fact said don’t do it this way, Remove the grout first and then gently pry off each tile. I think the grout on these tiles was some kind of caulking grout. It was rubbery and would have been difficult to remove. The tiles were stuck on with mastic and no amount of gentle prying would have taken some of them off. So I wound up with lots of torn and damaged drywall.
I researched repairs and many trades type folks said cut it out and replace it. But I was not that excited about cutting out all that drywall. The problem with torn drywall is that it has been severely weakened. To reinforce the drywall there were several suggestions. One was just to fill it in with drywall mud. Another to use a cement patch first. Then I found the suggestion to use Bondo household putty which is an epoxy and very strong. I liked this idea the best as it is fast drying and could keep the drywall from falling apart when mastic is used to install the new tiles.
I used a paint stick to smooth the bondo into the torn areas of drywall. The instructions are to fill the area below the surface of the drywall so it can be mudded and taped to fill in and create a smooth surface. Some areas of the drywall were too damaged to fill in with the putty so I cut out the broken drywall for new pieces.
A layer of drywall mud and adhesive fiberglass tape were laid down to cover the torn paper and bring the bondo layer up to the surface. I used six inch tape to make this step easier.
It took a few hours to mud these damaged areas and cut patches and screw them in.
Even with only one layer of mud the repair is starting to look ready for new tile.
I will put on another layer of mud and do some light sanding. Then I will waterproof the mud with a layer of shellac based primer. GARDZ was recommended but Home Depot only carried B-I-N which is apparently similar shellac based primer.
This primer is for preparing the raw drywall mud for mastic for the new tile backsplash. I also bought adhesive remover to smooth the area behind the stove where there was a glued on vinyl backsplash that I removed too. The drywall is supposed to be as smooth as possible to prepare for new tile.