After you have grouted the ceramic tile in your bathroom, you’re going to need to apply a shower grout sealer. A grout sealer will prevent moisture from seeping through underneath your tiles where it will create mildew and mold, and it will also prevent the grout from getting discolored, crumbly, and allowing mold to grow in the cracks of such a porous material.
Sealing the grout will not only prevent this kind of damage, but it will also make cleaning your shower tile surface much, much easier to clean and maintain – after all, dirt can very easily get trapped in grout and become impossible to remove.
Basic ceramic glazed tiles will only require sealer on the grout joints, which means that choosing a silicone or water-based penetrating sealer is your best option.
A penetrating sealer soaks into the pores of the grout, reducing the grout’s potential for absorbing foreign compounds that could damage or stain the surface. Penetrating sealers tend to be composed of latex or silicone solids which are suspended in a base of water, and after application, the base evaporates and leave the solid latex or silicone inside the grout pores.
Step 1: Preparing & Cleaning the Surface
1) Before cleaning the tile off, allow the grout to sit for at least a few minutes. When you are able to wipe grout off the surface of your shower wall with a damp sponge without grout being pulled out of the joints, you can clean until just a light haze remains on the tiles. Continue to use light strokes, moving diagonally, rinsing out the sponge often in a separate sponge bucket.
2) Wipe parallel to the grout joints to clean them and ensure their shape remains. Remove your grout until it is just below the rounded edges of the tiles, and press in some small amounts of grout if any voids appear during this process. Wait at least 10 minutes before moving on.
3) Get rid of the grout haze by using a soft, dry cloth. Use a very mild, green abrasive pad to scrub off any spots that refuse to come off – but remember to be gentle as to not scratch the tiles. Hopefully, you didn’t allow any grout to cure while on the surface of the tile – if you did, it is possible that it won’t come off at all unless you use an acid solution, which will ruin your entire grouting job.
Step 2: Just Before You Seal
4) Caulk the shower joint before you seal! Overfill the shower joint with caulk, run your finger under water, and then draw it along the caulk line to smooth it out. This should also level it to about the same depth as your grout joints. If you’re nervous about using a finger, there is a small plastic tool that you can purchase which is designed specifically for smoothing and evening out caulk lines.
5) You must then wait at least 48 hours, if not longer, before actually applying the shower grout sealer. The grout must have time to completely cure and set before being sealed, lest you compromise the job. Once you start applying the shower sealer, clean any and all spills immediately with soapy water – sealer can becomes quite slippery if it sets on the floor of the shower or tub.
Watch out; if you get sealer on any of the tiles, clean it up as soon as you notice. Sealer will not come off your tiles if you allow it to set, and will result in a haze that sets over the tiles – and it looks awful.