Updated: Mar 24
So, you're ready to seal the grout between your tiles? Follow these simple steps and before you know it, you'll have a cleaner and more aesthetic bathroom.
What Causes Discoloration in Bathroom Tiles?
Cement-based grout is porous. That means water, oil, grease and liquids can seep into the grout and cause discoloration, even if you keep your tiles clean.
How To Prevent Grout Discoloration
We recommend sealing grout during the initial tiling job and as-needed thereafter. This will create a strong barrier to prevent grout discoloration and stains. Sealant may be applied to floor and wall tiles on an annual basis-- and more often on shower grout and/or on the bathroom backsplash.
Let's Get Started!
Clean & Repair Grout
Be sure to clean your grout thoroughly before applying any sealant. Do this by scrubbing away any dirt/grime with a toothbrush dipped in soapy water. To lift and remove stains, use a vinegar and warm water solution with a 50/50 mix. This is the time to also repair any cracks or crumbling in the grout lines. Once you've cleaned the grout, let it dry for 45 minutes or so before applying the sealant.
Choose a Sealer
The second step is to choose a sealer. You need to consider the type of tile and the location of the tile. Read labels carefully. The product label will indicate the best product match for your tile material (stone, ceramic, marble, etc.) Also pay attention to the moisture-- note if the tile is in a high moisture area in a shower, or a low moisture area on a wall or backsplash. This will determine if you require a penetrating sealant or a membrane-forming sealant.
Penetrating Sealers use a water or mineral spirit base that lets the formula’s tiny particles of latex or silicone penetrate the granular structure of the grout. As the porous grout absorbs the sealer, the particles of latex and silicone fill in all the gaps, keeping moisture out. These sealers are the best choice for use in especially damp areas such as bathrooms, spa areas and showers.
Membrane-Forming Sealers create a coating on the surface of the grout that resists water permeation. These sealers work well in kitchen areas but we do not recommend for bathroom use. membrane-forming sealers won’t allow water that’s trapped underneath the tile to evaporate, which can cause mildew problems. These sealers may feature pigments, allowing you to change the grout color. While membrane-forming sealers are good for unglazed tile like stone, they won’t adhere to glazed tiles, such as most ceramics.
Choose a Sealer Applicator
Aerosol spray-on sealers are commonly used for convenience, but they may not be the best choice for your project. Thin Grout Lines: If you have very thin grout lines and unsealed tiles, use a sponge to easily seal larger sections of your bathroom (walls or floors) by wiping over both surfaces at once. Glazed Tiles: For glazed tiles where the sealer won’t adhere, use an applicator brush or specialty applicator bottle with a rolling wheel on top to seal only the grout lines. As with any project, be sure to review all of the manufacturer's product directions before you begin work.
Apply the Sealer
Apply the sealer in small areas at a time, working left to right. A steady and focused application will ensure your grout lines look consistent. Plus, you will get the best protection from your sealer! It's always a good idea to keep a dry cloth nearby to immediately wipe off any excess sealer. Be sure to avoid drips wherever possible and remove any excess sealer from the tiles before it dries (typically 5-7 minutes of application.) Otherwise, you'lll end up with a dull filmy residue that's very difficult to remove.
Apply a Second Coat
For best protection, the rule of thumb is to apply 1-3 coats of sealer. Wait at least one hour after your first coat dries before applying the next coat.
You can test the surface with a few drops of water after your second coat is completely dry. If the liquid doesn't bead into droplets, apply one more coat for the best results.
Whether you've applied two coats or three, you'll need to let your tiled space dry completely. Again, check the manufacturer’s label as some sealers require 24 hours to cure while others take up to 48 hours. Once you've successfully applied these steps, you can step back and appreciate your work.
Who doesn't want to look at clean tile and grout lines free of discoloration? After a little patience and determination, you'll now spend less time cleaning your bathroom tiles and grout and more time enjoying the clean new aesthetic!