When a ceramic tile job begins to look old and dingy, before you give in and install new tile, you should consider simply removing the grout from the seams and packing them with fresh, new grout. Provided the tiles themselves are in good condition and are still solidly adhered, regrouting the tile will make the entire installation look brand-new.
It's also quite an easy job. It requires no special skills, just a little bit of your time and the correct tools and materials. It takes about two hours to remove grout from 16 square feet of 6-inch tiles (about the area of a kitchen backsplash), and another hour, or so, to apply new grout. The required time, of course, increases if you have larger areas or if you have smaller tiles, which means more grout lines. But the techniques are not difficult, and you can save lots of money by doing this work yourself.
Regrouting is a two-step process by which you first remove the hardened old grout from the seams, or joints, between tiles with an oscillating tool (ideally) and some manual scraping. Then, you mix up some new grout and apply it to the tile with a grout float and clean it up with a sponge. Once the grout is dry, you wipe away its hazy residue from the tiles.
Removing old grout can be dusty. If necessary, you can hang plastic sheeting around the work area to confine the dust. Use a shop vac to suck away the debris while you work, and be sure to wear a dust mask to protect your lungs.
Equipment / Tools
- Safety glasses
- Dust mask
- Oscillating tool with grout removal blade
- Shop vacuum
- Small flat-head screwdriver
- Utility knife
- Margin trowel
- Grout float
- Grout sponge
- Soft cloths
- Powdered or premixed grout
- Grout haze remover (optional)
Grind Away the Old Grout
Fit an oscillating tool with a blade designed for grout removal. Most manufacturers sell blades designed for this purpose—usually, these are blades impregnated with fine diamond chips that make quick work of pulverizing hardened grout.
Turn on the tool and move the blade along the grout joints, holding the blade perpendicular to the tile surface. Work patiently, and take care not to allow the blade to nick or chip the ceramic tile. On the first pass, your goal is to simply remove the bulk of the grout—don't worry about removing every bit of grout on the first pass.
As you work, pause frequently to remove dust and debris with a shop vac.
Manual grout saws can be purchased much cheaper for small jobs or if you have the time and patience.
Clean Up the Grout Lines
Once you have removed most of the grout, make another pass with the oscillating tool to clean up the grout lines. This time, angle the blade slightly in order to get close to the edges of the tile. Make sure not to linger on the edges of the grout lines, as this can easily damage the tiles. The grout will crumble quickly under the action of the blade. Do not force the blade if you find that some areas do not easily grind out—these bits of grout will be removed manually later. Vacuum the grout lines as you go.
Remove Remaining Grout Manually
Where the power tool fails to remove all traces of grout, follow up with a flat-head screwdriver or utility knife (it's fine to use a dull blade) to carve out any remaining bits of grout. Take care not to scratch the faces of the tiles.
Do not pry the screwdriver against the edges of the tile, as this can easily chip them.
Once the old grout has been removed from the seams, use a shop vac to thoroughly clear out any dust and debris. The grout lines must be completely clean and dry before filling them with fresh grout.
Mix the Grout
Tile grout is available both as a dry powder that must be mixed with water or as a premixed semi-liquid paste in tubs of various sizes. Mix powdered grout in a small bucket, using a margin trowel.
If you are mixing dry grout, begin by adding 1/2 of the recommended amount of water in a plastic bucket, then add 1/2 of the recommended amount of dry grout powder. Mix thoroughly, then add more water and more grout powder gradually until you have a full batch, or enough to cover about 3 to 4 feet square. The proper mixture should have a smooth, paste-like consistency that is just barely pourable.
Some grout may have instructions to allow the mixture to sit (slake) for a short period before applying. If so, follow the manufacturer's instructions regarding this.
Fill the Grout Joints
Scoop up a load of grout with a rubber grout float, and smear it onto the tile surface. Spread the grout over the joints, holding the float at an angle of about 60 degrees and pressing the grout fully into the joints. Work in alternating directions to make sure the joints are completely filled. Gather any excess grout and move it to the next area of tile, or reload the tile as needed. Repeat the same process until all of the joints are filled.
The grout float should be moved diagonal to the joint lines to insure a uniform fill. If tiles have a rounded or beveled edge the joints may need to be tooled. Tooling is the process of removing the upper layer of grout leaving a thinner professional looking joint. The are special tools that can be purchased for this or a round eraser on a pencil can be drug along the joint lines of the slightly dried grout.
Sponge the Joints and Tiles
Once all grout lines are filled, use a moistened sponge to remove excess grout. Make sure the sponge is barely wet—too much water will pull grout out of the seams. Lightly stroke the sponge across the tile surface without pressing too hard.
This is a slow process. Continue to clean out your sponge and move them across the tile surface until all excess grout is gone. Don't worry about cleaning the surfaces of the tile completely; that will come next. Rinse the sponge frequently in the water, and change the water as it becomes dirty.
Sponging should also be done diagonally to the grout joints.
Remove the Grout Haze
Once the grout has dried completely (or as directed), a faint haze will still be present on the surface of the tiles. Use a soft cloth to buff the surfaces of the tile and remove any remaining haze. If you wish, you can use a purchased haze-removing product to polish the tiles.
Standard grout that comes in powdered form should be sealed for stain-resistance (after the grout has fully cured). Many types of premixed grout do not need to be sealed.