Painted shower tiles, whether simply painted a new single colour for a quick update, hand-painted individual tiles added as a feature, or a painted mosaic or scene, will need to be protected from the water and humidity by a sealer. There are many options for sealers. They come in oil-based and water-based formulas. Depending on the formula, they can applied by spraying, painting, rolling and brushing. After two or three coats of sealer are applied, the painted shower tiles will be protected for months or years depending on the use. Shower tiles on the floor or where water is constantly applied might need to be sealed more regularly than a border of painted tiles along the ceiling or top edge of a shower.
Clean the tile. If the tile has been painted within the past few days, a damp cloth gently wiped over the design after it is fully dried will be sufficient to remove any dust particles.
If the tile has been in the shower for a longer period of time, it may be necessary to use a gentle nonabrasive cleaner on the tile.
Clean the grouted areas well.
Using a toothbrush, gently scrub the grouted areas so that there is no mould, scum or discolouration. When the tiles are sealed, it is likely that a little sealer will get on the grout. If the grout is not very clean, stains could be sealed in permanently.
If the grout is severely stained or discoloured, it may be necessary to bleach the grout, stain the grout or paint the grout with a grout painting tool or kit prior to applying the sealer to the painted shower tiles.
Allow the tiles and the grout to completely dry.
Sometimes this can take a few days depending on how wet the grout was, whether the grout has been sealed or not (which would have provided a protective coating for it), and the level of humidity.
Tape off the areas like painted walls or floor near tiles that will be sealed so that sealer is not applied to a wall surface or another surface where it is not desired.
It is helpful to tape along the grout line with a sheet of newspaper taped under to prevent sealer from seeping into the grout below a border or onto the floor. The newspaper will protect against any drips, splatters or spills.
If the sealer application is high, spread some newspaper over the floor to catch any drips.
Select the sealer that is desired.
There are tile sealers available at home improvement stores and at art and craft stores. Natural stone will need a sealer that works on natural stone. Glass tiles will need a sealer that will adhere to glass. Ceramic tiles can have urethane, polyurethane, enamel glaze and a few other sealers that are offered at either home improvement painting departing or arts and crafts supply stores.
Most sealers will require a brush, roller, or foam application.
Some sealers are able to be sprayed on to the tiles and grout. Sealers that are applied by hand will allow more control, the ability to just seal the picture, the tile, or the whole area.
Apply a single coat of sealer using the tools as recommended in the directions.
The directions will detail the best tool to use to prevent lines or clumping. The directions will also explain whether to apply only in one direction or not. Pay close attention to these details; they will make a huge difference in outcome of the sealing application.
Allow sealer to dry completely and then reapply a second coat.
It would be highly recommended not to use the shower until all the coats are finished so that no residue of any kind gets trapped between the layers of sealer.
Check sealed painted tiles for wear every few months. Follow the steps to clean the tiles and reapply the sealer before wear becomes severe, which is where the worn tiles or areas have a different depth than the others.
It is usually necessary to reseal the tiles depending on their location and use. Tiles underfoot or low on the shower may need to be resealed every 6 months, while other tiles may need to be resealed every few years. Do not allow some sealed tiles to wear through excessively before resealing or they will look uneven. Reseal the tiles as needed individually, if necessary, to keep them all well maintained and matching. There is an old-fashioned look for some painted tiles where only the painted area is sealed using a brush; this gives added gloss and dimension to the picture only. Read the finishes well to determine the final finish--gloss, semigloss, matt--and also whether the finish will tint or yellow. There are finishes that are water-based and completely clear. These will need to be reapplied more often; however, they do not add any tinting or yellow with age like other stronger sealers.
Use gloves when using sealers so they do not get on the skin. Use a mask when using sealer so that it is not inhaled. Good ventilation is necessary when using sealers inside. Some sealers are flammable or combustible; read and follow all safety precautions.