Grout is the goop that fills the spaces between tiles to create a finished look and keep out water. Whether you are just installing tile that needs grouting or you are replacing aging grout, cleaning the tile is essential. Dust and old grout fragments in the cracks will prevent your new grout from setting properly. Exactly how to clean depends on the circumstances.

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How to Clean Tile Before Grouting

Cleaning Tile Joints Before Grouting

When you are planning on grouting tile, it may not seem very important to clean out the cracks between the tiles. With new tile, you may feel certain that the cracks between tiles are clear since you just put them in a few days ago. With older tile, new tile will get smudged into all the available crevices, so it doesn't seem to matter if a little debris remains.

In fact, cleaning tile joints before grouting is essential. The very purpose of grouting is to fill those spaces once and for all with a paste that will harden into a waterproof seal. Both dust and old grout pieces can prevent a good set. Cleaning mortar out of grout lines and taking steps to remove thinset between tiles can help.

Cleaning New Tile Joints

The first step to cleaning new tile joints is cleaning mortar out of the grout lines. Since you used mortar to cement the tile in place, some may pass up between the tiles, even in the most careful application. You'll do best to remove this mortar just after installation while it is soft. Get a tile spacer tool the same width as the grout lines and you can clean as you lay tile.

When you are cleaning tile joints of dust before grouting a new tile installation, patience is key. Before tackling the job, you need to wait long enough to allow the mortar or tile adhesive to dry completely. Check the instructions and if you aren't sure of the correct period, give it another day or two. Once the tile adhesive is dry, use your vacuum cleaner to get out dust and other construction debris that may have lodged in the cracks. Then, wipe down the tile itself with a sponge dipped in a mixture of dish soap and water. Finally, use a sponge dipped only in water to rinse. Allow the area to dry completely before applying new grout.

Cleaning Old Tile Joints

If you are regrouting a tiled area, you have a longer task ahead of you. Cleaning old mortar out of grout lines or trying remove thinset between tiles is not work that takes a minute, so allow yourself plenty of time. It will speed things up if you collect a variety of tools to help you.

Be sure you have a grout saw. This tool has either serrated metal teeth or an abrasive carbide grit, both of which are very effective in scratching out old tile if you pull it across the grout gently. A grout saw or grout removal bit for a rotary tool works even faster. Another tool to try is a straight-blade scraper. This is particularly good at removing the caulk bead between a bathtub and the first row of tiling. Putty knives or thin-blade screwdrivers can also be effective. Remove the old grout chunks and all fragments, but take care not to nick or scrape the tile surface. Once that is accomplished, vacuum well and then clean the tile faces with dish soap and water.