DOES YOUR GROUT NEED SEALING OR RE-SEALING?
Have you scheduled a tile and grout cleaning job or done it yourself and wondered if you need grout sealing as well?
It is relatively simple to find the answer to your question. Simply sprinkle a few drops of water at several places around your tile. If areas of your grout soak in the water immediately, your grout should be sealed or re-sealed.
WHAT IS GROUT?
Grout is used to fill the seams between tiles. Most grout is called 'sanded grout' because the grout contains sand, which is a good and inexpensive material to use. Unfortunately though, sand is porous and therefore grout is porous. It is this porosity that makes it necessary to seal the grout after the majority of tile applications, as well as re-seal the grout when needed.
After grout has been applied and has dried, but has not yet been sealed, it will absorb water and any other liquid, as well as dirt, mildew, and other contaminants through its microscopic pores that act like a sponge. Obviously, this is not a good situation for a shower wall or bathroom floor but can be a problem in any area where tile has been laid and grout has not been sealed or the seal has worn off.
Please note: There is a type of grout which is epoxy-based called epoxy grout or pre-sealed grout. This type of grout does not need sealing because it actually sheds water. It is relatively expensive and difficult to mix so is not used as much as sanded grout.
WHY WASN'T MY GROUT SEALED BY MY CONTRACTOR?
The usual answer to this is--If a sanded grout was used and it was not sealed, it may be the fault of the contractor.
To seal the grout in a new installation means returning at another time because the grout must be completely dried after installation. This can take as much as 30 days. Many contractors do not want to, or may not have the time in their schedule, to return to the site to do this.
WHY DOES MY INSTALLED GROUT NEED SEALING IF IT WAS SEALED AFTER INSTALLATION?
Existing tile may need to have the grout sealer reapplied. Bathroom wall tile and tile kitchen counter tops especially, may need to have the grout sealed more frequently.
Since grout is porous, spills may seep in if not cleaned up immediately. Colors from liquids such as fruit juice or tea and coffee may remain after the liquid evaporates, staining the grout. Oils can also seep into the grout. To remove these stains, the old grout may need to be chipped out and replaced. NOTE: There are some types of grout available that are non-staining.
PROTECTION FROM MOLD & MILDEW
Grout is not as resilient as the tiles surrounding it and applying grout sealer can provide good protection, especially against mold and mildew as in a bathroom situation. The combination of continuous water exposure and warm temperatures can cause slow chemical changes in the structure of the grout. The minerals that compose the grout structure can dissolve away, allowing water to go even deeper.
It is important to note that as the minerals in the grout dissolve, the alkalinity of the grout is reduced, eventually allowing bacteria to survive and reproduce as well. The water may reach the mortar at the base of the tile, compromising the drywall backing and the entire tile assembly.
IF MY GROUT NEEDS TO BE SEALED, HOW OFTEN SHOULD IT BE DONE?
Please continue reading here for the answer and for more information about grout sealing.