All about sealing grout

Do I need to seal grout? Expert advice and directions 

If you’ve wondered, “Do I need to seal grout?” this article is for you. Don’t miss out on why this important step will help preserve your tile and keep it looking great. Read on and learn to seal grout like a pro.

Do I need to seal grout? Why this is an important step

Have you just added a new tile floor, countertop, or backsplash? Or maybe you’ve upgraded your bathroom walls or some other part of the house. The tile is down, the grout is dry. Is it necessary to seal grout on tile?

Sometimes, this step gets forgotten, but there are good reasons to put a quality sealer on your grout. It’s also good to refresh the grout on existing tile surfaces from time to time with a coat of sealer. Why?

Most grout, whether sanded or unsanded, is porous and will allow water to seep in. This may not seem like a big deal, but if it gets damp in between your tiles repeatedly, over time you may have issues. Grout may eventually become discoloured or mouldy, the substrate below the tile may begin to degrade, or the area might develop an odour. If this goes on long enough, the grout may even begin to loosen and chip out from between the tiles.

The simple solution is a quality grout sealer. This is not a caulk or sealant used for corners and gaps but a liquid waterproofing product that treats the grout to make it water repellant.

How to seal grout on tile: Product selection

When choosing a grout sealer, you will find surface sealers and penetrating sealers. For many uses including lower trafficked areas, surface sealers are fine. They provide a barrier that prevents dirt and moisture from getting into the grout. 

Penetrating sealers work best in wet areas, like showers, tub surrounds, and other areas frequently in contact with water. Penetrating sealers soak into the grout and dry, providing better protection against moisture.

There are also a variety of application methods. Grout sealer may be brushed on or rolled on with a small paint roller. You will even find some sealers that are dispensed right from the bottle. For larger areas or quick coats, you may choose a spray-on variety.

How to seal grout tile floors or walls: Prep work

Whenever you plan on sealing grout on tile, some preparatory work will be needed first:

  • Ensure new grout is fully cured before sealing it. Most manufacturers recommend 48–72 hours.
  • Existing grout must be thoroughly cleaned before resealing. Make sure to remove dirt, stains, mould, or anything that makes the grout look dirty, since most sealers are transparent. Soap and water and a small, stiff-bristled brush work well, or use your favourite tile cleaner. 
  • Remove stains with vinegar and water or household bleach and water.
  • Protect baseboards, walls, fixtures, and surrounding areas from encountering the sealer. This is especially vital if you are spraying the sealer. You can use masking tape and plastic or paper to cover these areas. 

Simple directions: How to seal grout on tile

Once you are ready to begin, follow these steps to properly seal grout on tile:

  1. Apply the grout sealer using a brush, roller, or by spraying. Aim for even coverage of all joints. You may find it best to work line by line in a logical way to avoid missing spots.
  2. Clean up any sealer that has spilled onto the tiles (always abide by the printed directions on the label) within about 5 minutes of application. Using a clean cloth will do the trick.
  3. After the first coat of sealer is dry (typically about an hour), apply a second coat of sealer in the same manner. 
  4. Allow 24–48 hours for the sealer to fully dry before using the area. 

Test the seal by sprinkling a few drops of water on the sealed grout. If the water beads and stays on the surface, the grout is properly sealed. If the water is absorbed, you should apply another coat of sealer.

If you happen to miss a spot when cleaning, and the sealer has dried on the wall or tile, you may see a white stain or slight discolouration. Fear not, just apply a bit of the liquid sealer to it and wipe away with a clean cloth.