Things You'll Need
Dremel Tool (If you have one)
Fine point chisel
New tiles (if you break one)
Silicon to seal around the drain
Replacing a drain in a tiled shower is a project that can be done by the average homeowner. It will require a few specialized tools and quite possibly replacement tile. But this is not near as bothersome as having to pay a contractor to come in and have to do a major restoration for damage to a floor and ceiling because of a leak.
Replacing a Shower Drain
Clear all of the grout around the drain. You can use a Dremel tool or a grout saw. Grout saws have teeth on the end of them and remove the grout. Remove only enough grout that will allow you to fix the drain. Do not do unnecessary tiles.
Pry the tiles up. Be careful because you do not want to break them. You will see the drain housing. Remove the drain. It will be glued so you will have to pull hard or pry it off.
Clean the drainpipe. Apply pipe cement to the pipe and the inside of the new drain. Put the drain over the drainpipe. Allow an hour to dry.
Replace the tiles. Use the tile cement and apply it to the tiles like peanut butter. Make it about 1/8 of an inch. Push the tiles down. Allow them 24 hours to dry.
Grout all of the gaps except the part around the drain. Use the grout float to push the grout into the gaps. This will assure an even surface. Allow the grout to dry overnight.
Seal the new drain with silicone. This will assure that there will be no leaks. You have to let this dry for at least 24 hours.
If you are replacing a tile shower drain, make provisions that you will be without a shower for at least 48 hours.