Ceramic tile grout won't stick in a shallow groove that's partially filled with glaze. Once the tile has been glaze fired, it's ready to accept grout. Note: Colored grout stains everything it touches!
Unsanded grout is excellent for bathroom floors and walls, as well as with ceramic tiles and marble. Natural stones perform well with this type of grout.
Tile adhesive is made specifically to bond tiles to the subfloor or the walls. Grout is used specifically to fill in the space between the tiles and further seal the spaces from water, bacteria, and dust. Though some of the ingredients may be shared between the two compounds, they are not interchangeable in any way.
The first point to consider is that the tile is properly installed, cleaned and ready to grout. The adhesive must have time to cure, or lime, and color can bleed into the grout. The tile and the joints must be clean of dirt, trash, and pieces of spacers. Any debris left in the joint can show up in the grout.
Optimally, no more than 30 minutes should pass for the initial wiping off of excess grout. This process must be performed gently with a wet grout sponge during regrouting.
Too little thinset, the glue that overlays the mortar, results in it pulling away from the tile. Under the tile, gaps of air develop. When water gets added to the cement hydration after it begins curing, the grout weakens and crumbles soon after.
Sanded grout is recommended for any install using ceramic, porcelain, granites, flamed or brushed marble, terrazzo, rock pebbles or meshed pebbles with a 1/8" or up grout joint. Having this spacing in your tile means there is more room for grout error.
If you use Grout Release, you'll apply it 30 minutes prior to grouting. It's very important to make sure the tile is both clean and dry prior to application. Grout Release is ready to use directly out of the bottle. First, shake the bottle prior to use.
The humidity in the environment, and the temperature of the room will also affect the drying times. The shortest time after laying tile that you can grout is 24 hours. However, it is much better to wait at least 48 hours before grouting. This is to give the mortar ample time to set and dry before pressure is applied.
Epoxy grout can be used on porcelain tile. By using epoxy grout you'll be sure to use the highest quality grout in the market that will last a lifetime.
What Can I Use Instead Of a Grouting Tool? For most tiling jobs a grouting tool is the ideal choice for getting a smooth uniform finish on larger gaps i.e. 5mm or larger. But if you are using 2mm or 3mm tile spacers and don't have a grouting tool to hand you can use the top of a round pencil to get the uniform finish.
If you try adding new grout over your old grout, the new mixture will not properly adhere to the existing grout or tile edges, leaving your shower open to water damage.
ANSWER - It is possible to grout over existing grout if there is enough depth to do so. 1/8 inch depth may or may not be adequate depending on the type of grout used. A latex modified grout may work, but you have to properly clean the existing grout to ensure the new grout adequately bonds.
The surface of porcelain and ceramic tile do not require sealing, however, it's important to note that even though your porcelain or ceramic tile does not need to be sealed, the grout used during installation will need to be sealed and maintained.
Dampen the substrate and tiles
The use of water is an important part of the entire installation process. Before grouting, use a clean sponge with potable water to dampen the substrate throughout the tile installation. Next, dampen the edges of the tiles with a light water spray bottle.
Before wiping off any excess product, let the grout harden and then test it with your finger. Scrubbing the wall will be ineffective as it just moves the product around, instead of cleaning it effectively. Instead, you'll want to use a damp, not soaking wet, sponge to clean the entire area in long, continuous strokes.
Epoxy grout is water resistant and made from resins and fillers that help it work like a sealing adhesive. Epoxy grout is a better choice for showers, kitchen, bathrooms, and other damp areas because it is stain resistant and requires no sealing, unlike cement-based grout.
3/16" We recommend a 3/16" grout size for our Ceramic Tile. This thickness leaves room for the natural variation in size, and the perfectly imperfect edges of handmade tile.
A premixed grout is the best grout for tile if you are looking for color consistency and a quicker installation. Premixed grout saves time because you can open a bucket and start grouting immediately.
As mentioned, silicone works well in places where shifts in pressure can cause your grout to crack. For most bathrooms, this means using it as a sealant for the joints of the shower tray and the bath.
Grout can crack when there's too much water mixed into the grout, which create tiny pinholes. When the grout dries, these pinholes make it easier for cracks to form in the grout. Too much water in grout can make the grout weaker. Grout can crack due to thinset (glue) that is applied over the mortar during installation.
The primary reason why grout deteriorates is that it was not mixed and installed properly. If too much water is added to the grout at install, it will not seal with the required density to withstand prolonged exposure to moisture and (most of all) water.
You can grout with your finger. First apply the grout with a float, then neaten the grout line by running your finger along the lines. Leave to harden off a little before wiping the excess grout from the tiles' surfaces. After you have wiped, check the lines and again use your finger to create a neat finish.