REGROUT BATHROOM TILE | BEFORE YOU BEGIN
Your tile grout might be mildew- or hard water-stained, which can make the bathroom look dirtier than it really is. You can first try bleaching the grout, using an old toothbrush as an applicator. If that fails, try carefully scraping away the top layer with a flat razor blade, then applying a tile sealer to keep it white longer. If there happen to be any hard water stains, you can first try scraping the excess residue off with a flat razor blade then finish off the rest with any good hard water spot remover and a nylon pad.
But if you see cracks in the grout, this is an indication that the grout has failed. Now is the time to deal with the problem. This project will cover how to re-grout the entire wall area. Often, only select areas will have grout that requires fixing. You can follow the same process for repairing certain spots as you would the entire wall. Plan on not using the shower or tub for at least three days. Grout needs about 48 hours to cure before you can apply a grout sealant, which takes at least another full day.
It’s fine to grout over cracked grout if the space is about the thickness of a dime. You may need to scrape out a little of the existing grout to accommodate the new grout, otherwise, there will not be enough room.
Be sure to use the right grout. Sanded grout is for spaces that are over 1/8″ thick and non-sanded grout is for smaller joints. Use the same grout that is currently installed, whether that is sanded or non-sanded.
Step 1: Prepare the Area
Place masking tape over the drain to keep out debris when you’re ready to work. Place a canvas drop cloth over the floor of the tub or shower to protect the surface from the sand-like grout that can scratch it. If you’re dealing with a bathroom where the wall grout has completely broken down, you’ll first need to remove the tub spout, faucet spout, handles, and trim. If you’re just spot repairing, you can jump in and start extracting grout.
If the tub spout screws off, twist it either by hand or with groove-joint pliers padded with tape to prevent marring the spout finish. If you have the type that slips over a copper nipple, use an Allen wrench to loosen the setscrew on the underside to twist-pull the spout off.
If the spout is stuck on, try inserting the blade of a large screwdriver or the handle of a pair of pliers into the spout opening to twist.
To remove faucet handles, first use a nail file or knife to pop off any decorative cap that covers the handle screw. Then, remove the screw with a Phillips head screwdriver and pull the handle straight out. With the handles off you can remove the trim by hand. First, unscrew the stem nipple (a cylindrical sleeve) from the valve and either unscrew or pull off the escutcheon (the flange that hides the rough hole in the tile). To free the escutcheon, you may need to score any caulk between it and the tile with a utility knife.
Step 2: Extract Old Grout
Use an abrasive grout saw to remove as much grout from the joints (the area between tiles) as you can. Some grout saws have teeth, while others have abrasive coatings on the blade. Use either type with care to avoid scratching the tile. This can be a time-consuming task; take your time and don’t rush it.
Use a shop vacuum to thoroughly remove dust. Use the wand attachment on the shop vacuum to get into the crevices. Then clean the grout with bleach or a mildew remover to remove all traces of mildew. Rinse and dry until there is no standing water in the joints, but try to leave joints slightly wet before you grout.
If the wall is bone dry, lightly mist the scraped out joints with water, before moving to the next step.
Step 3: Apply Grout
Just before you’re ready to grout, mix an appropriate amount by adding water slowly to the powder in a mixing container until the right consistency is reached. Grout should be just stiff enough so that it won’t pour out of the container. Then let it sit for about 10 minutes. Spread the grout diagonally across the tile using a rubber float (grout trowel). Hold the float at a 45-degree angle. Press the grout into all joints with the trowel, going over the area at least three times. Clear off excess by holding the trowel at a 90-degree angle and moving across the tile.
For a repair to a small area, you can use your fingertip or a rubber spatula to apply the grout.
If you’re new to the task, mix and apply the grout in two or three batches so it won’t get too stiff before you have time to work with it.
You need to allow the grout to set so it won’t be wiped out of the joint as you clean the tile. After a few minutes, test the grout for readiness by wiping down a small area using a damp sponge. Wipe off excess grout diagonally with the sponge. Leave a slight haze. Rinse and wring out the sponge often. Then wipe parallel until only the level below the tile contains grout. While wearing plastic gloves, fill any grout voids in the joints with your finger and smooth with a plastic straw. Wait for another 10 to 15 minutes and then wipe off the grout haze with a soft, dry cotton cloth. Do not allow grout to cure on the surface of the tile. If the haze has bonded, remove it using an abrasive hand pad. In some cases, if the haze has bonded, you may need to use a grout haze-cleaning solution to remove it.
Step 4: Caulk Tub-Tile Joint
Grout failure often occurs at the tub-tile joint. This joint should be caulked. Caulk remains flexible and allows for the inevitable movement of the tub when it’s filled with 100 pounds of water and people. Dig out damaged grout in the joint with a putty knife. Grout does not bond well with porcelain and cracks with movement. Soften old caulk in the tub-tile joint if necessary using caulk softener. Overfill the joint with caulk using a caulking gun. Then smooth and level excess with a wet, gloved finger, or a plastic caulking tool.
Step 5: Seal the Grout
Because grout is not waterproof, you’ll want to protect it with silicone grout sealer when you’re done. Allow grout to cure for at least 48 hours, and then use an old toothbrush to apply the sealer.
Grout sealer, if spilled, is very slippery. Use caution when applying it, and wipe up spills immediately using a soapy detergent.
That’s it! Your new tile grout should help update the look of your bathroom.