Plastic tile repair

We moved into a 100 year old home three months ago. It was an inheritance, and the heir did a lot of work before selling. The bathroom was freshly renovated, using red plastic tiles that I'm guessing were stored somewhere in the house. The tiling wraps all the way around the room, including in the shower.
Within a few weeks, we began to notice a few of the tiles pulling away from the wall. They are caulked rather than grouted, and seams are opening up between a few of them.
What should I do? Can I cut out the caulk and replace with grout? Am I going to have to redo the entire shower? My primary goal at this moment is to prevent further damage to the wallboard - I don't think we can afford to fully replace the tile right now.
  2 answers
  • Marion Nesbitt Marion Nesbitt on Jul 06, 2015
    Are these plastic tiles from way back? If so, they are a fire hazard. I would remove them all, clean up the mess and paint with a super oil-based enamel or melamine paint in the shower area.
  • Ed Held Ed Held on Jul 07, 2015
    The new all-in-one bathtub units simply mold existing area then install over the old surface with a completely new surface. Call around, I've forgotten the co.'s name but it's like re-do tubs- al-in -One with fiberglass siding. it fits right over the existing bad areas. Ed Held