Mix the grout powder (you can buy it at the home improvement store) with water. Use your fingers to apply the grout between all tiles. (You can also use a rubber grout floater). Remove excess grout.
Yes new grout can be installed on old grout. Make sure the old grout is thoroughly cleaned and then wet before installation. I do this all the time. There is absolutely no need to start over and given the quality of the install you have had so far I would say that starting over might introduce more issues.
Can you spot repair grout? Spot repairing grout is not only possible, it's also a great way to fix cracked or crumbling grout lines. Simple remove the damaged grout, wipe down the area, prepare the new grout, then apply. Wipe away any excess grout and allow the new grout lines to dry and cure.
For the areas of missing grout, it would be best to chip out any adjacent grout that is loose and remove it. You can then patch the area with a mortar tinted to the correct colour with oxide.
Fortunately, the holes in the shower's grout can be repaired. If the grout is in poor condition, you may need to replace it completely, but if the grout is in overall good condition, fixing the holes might be sufficient. One thing is certain: the holes in your shower grout should not be left unattended.
Generally, you should be okay to mix up some grout and touch up any trouble spots in your new grout. Stuff like pin holes, scratches or low spots can be touched up with fresh grout the next day. The trick is to blend in the new grout with the old so make sure you mix it the same way that you mixed it the day before.
If your grout is cracked or missing in spots, you'll need to do some prep work before you fix the grout between tiles. To repair cracks, use a caulking gun and silicone caulk designed for wet areas. Fill cracks flush with the tile surface or slightly below.
You can remedy this by using caulk to fill in the cracks and restore the look of the grout. First, remove all loose and cracked grout with a grout saw or Dremel tool. Apply the caulk gently to the cracks, smoothing it down with a plastic spoon. You can also wet your fingers and smooth the caulk by hand.
Do not attempt to apply new grout over the damaged existing grout. Just applying new grout over the existing grout is called skim coating grout and the new grout will not properly adhere to the old grout. Over time the new grout will start flaking and chipping away. There are two ways to effectively remove old grout…
Choosing the correct grout is a basic step in the process of regrouting over existing grout. The most common grout types are cementitious (which is unsanded or sanded) or epoxy (which is also sanded or unsanded).
Grout comes in many varieties, and it's generally considered to be safe once it has been applied and dries.
You would also notice that adding new grout will not be aesthetically pleasing, as the new layer would be thin. This means that your old grout will be seen beneath, and if you were to only treat one area, you would see the difference in the “repaired” area versus the area that you did not add grout to.
If any gaps or holes appear, apply more grout with your fingertip. Sponge off any excess. Allow the grout to dry for several hours, preferably overnight.
In fact, if you see your grout lines are deteriorating, or even if you just want to update the look of your tiles, you can make a weekend project of it and have new grout in no time. Not only does it save you time when you apply new grout over existing grout, it saves you money.
Grout pens will only temporarily cover your grout's discoloration. That's probably why they are the cheapest option available. We run into the infamous grout pen issue nearly every other week. The project usually goes awry when the homeowner applies the grout pen to the grout and some bleeds over onto the tile.
Baking powder is actually a tried-and-true way to clean bathroom grout. First, mix some baking powder with water to create a thick paste. Then apply this paste to the grout and let it sit for about an hour.
Excess Grout
Grout protruding from between your tiles is a clear sign of an amateur or rushed installation job. If the grout hasn't fully hardened, you can scrape it out with a wooden, preferably oak, stick. This will remove the grout without scratching the tiles.
As go-to grout and tile care specialists, The Grout Medic truly wants what is best for your tile. Waiting too long to wipe grout could result in unsightly grout haze. Don't wait too long to wipe off grout!
To remediate this type of problem to make the grout to be more consistent in color there are products called "grout colorants" that are epoxy based and match some of the typical grout colors. After properly preparing the existing grout joint you paint it over the joint which could be a bit tedious of a process.
It is surprisingly easy to get caught up in the moment and apply too much grout, without realizing it until the grout has set. If this happens, it can be fixed up to a week later by repeatedly wetting, scraping, and chiseling the grout in order to file it down and shape it.
There are a few different materials to fill in gaps in your grout, but we recommend using a premixed grout. Using a premixed grout is the easiest way to fill grout gaps, as mixes come in a wide variety of colors.
If cleaning is not possible after 24 hours, then you should not leave your grout haze uncleaned for more than 10 days, otherwise, it will be even harder to remove. Finally, you need to be sure you have the right cleaner for your tile material. Acidic cleaners, for example, should not be used on stone.