Shower valve and tile replacement. - DoItYourself.com Community Forums
bathroom - How do I secure the shower valve without removing tile? - Home Improvement Stack Exchange
please help...shower/ tub valve question
How to replace the shower faucet without breaking the tile
Can I replace a shower valve on my own?
How do I get into the wall to access the valve?
Why are there two valves to shut off if there's only one water line?
Videos
I have this type of faucet valve https://imgur.com/gallery/oRMfjvd in my guest bath. The faucet knobs for these break at the slightest force and I’ve already replaced few times. My question is there a way I can replace the ‘white plastic’ valve with the metal types and thus install the faucets with handle?
You'll have to be creative, but the best solution is to open the wall on the opposite side behind the valve. Hopefully you have drywall or a closet and not an outside wall. Drywall repair is cheaper and easier than tile repair. In many areas it is code to have an access hatch to reach the bathtub trap, so you may be able to reach it from there.
Other option is to bust out as few tiles as possible. You should have a few spares from the tile work, or if it is recent you may be able to buy a few to patch the damage.
Adding to mfaver answer. You could also take the flanges off the taps and shower rose and try and pump silicon or another non-porous substance into the annular space, once it sets it will hold the shower valve in place against the wall and tile backing. Not the most professional solution but it avoids opening the wall up.