You can add a painted finish to ceramic bathroom tile if you properly prepare the surface prior to application. Unlike drywall, untreated ceramic tile is ill-suited for adhesion. If you add paint to under-prepared ceramic tile, the new finish will eventually flake. Learn the proper way to condition ceramic tile for better adhesion. Choose a particular paint based on the location of the bathroom tile.
New finishes will not adhere to unwashed ceramic tile. This is especially true of tile located within a shower stall. Dirt and soap scum greatly inhibit adhesion and tend to promote rampant peeling. Before doing anything else, thoroughly scrub the ceramic tile clean. Ordinary soap may do little to remove stubborn grime and could leave a residue of its own. For best results, use a clean-rinsing trisodium phosphate cleansing agent.
No type of ceramic tile will accept a painted finish unless it is properly abraded. Before you even think about applying a primer base or painted finish, scour all of the ceramic bathroom tile with a 100- to 120-grit sandpaper. This will roughen the tile and improve its adhesive qualities. This step is critical; don't skip it.
Once the ceramic bathroom tile is abraded, it will take on a primer base. Before you settle on a specific type of primer, consider the location of the tile. Latex primer is well-suited for ceramic bathroom tile located outside baths and showers. Unfortunately, it may not prove as durable inside baths and showers where it will be subject to consistent moisture exposure. In this case, apply an acrylic primer.
If you've properly abraded and primed your ceramic bathroom tile, it will readily take on a painted finish. Select a particular paint based on the location of the tile. For wall tile located outside the bath and shower, use an eggshell, satin or semi-gloss latex paint. These paints won't prove durable inside a bath or shower. For this type of tile, choose either a durable acrylic enamel or epoxy paint.
High humidity can cause problems during the application and curing process. Don't run the shower for a full day before and after the application process.