The Grout has microscopic pores that dirty shampoo and body oils like to embed themselves into. This is the kind of stuff that mold can feed on!
The first step in sealing your tile shower is to thoroughly clean and re-open the pores of the Grout/tile. I recommend hiring a professional to do the cleaning and sealing but if you are a DIYer then we will outline some tips for you below:
Cleaning The Tile & Grout
Go to your local tile store and purchase a good tile and Grout cleaner/degreaser. Follow the instructions carefully to thoroughly clean the tile and Grout. Be sure to rinse off all the cleaner from the surface. It is very important to thoroughly clean the grout. You would not want to trap in the dirt and mold.
Apply a Clear Seal on the Grout
There are sealers that are solvent-based and water-based. Check out this article on the sealers. If you use a solvent-based sealer you must wait 24 hours for the grout to completely dry before applying. If you go with a water-based sealer, the grout can be wet when applied. Both sealers are very good and neither one is better than the other. We prefer to use the water-based sealers and have very good results with them. The clear sealers come in a bottle usually with a wheel or brush on top. Simply brush or roll over the top of the grout line extracting the sealer on the grout. Allow the sealer to sit for up to 5 minutes to completely work it’s way into the pores of the grout.
Now, if you use a solvent-based sealer, you must NOT allow it to dry on the tile or it will leave a haze. Should this happen, simply put more sealer on to reactivate it and wipe it off. Water-based sealers will evaporate off the tile surface. And lastly, buff the entire surface to a shine.
In order to protect your newly cleaned and sealed grout in your shower, there are a couple of tips you should follow.
1. Keep a squeegee in the shower and be sure to remove all water off the walls and glass before exiting.
2. Leave the shower doors or curtain open to ensure proper ventilation and reduce the opportunity for mold and mildew growth.
3. Reseal the grout every year to keep your shower looking it’s best (repeat if necessary)