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Expert Answers
Is it Possible to Grout over existing grout?
QUESTION
Is it possible to grout directly over existing grout and have a proper permanent fix?I had approximately 2,000 square feet of porcelain tile installed in a new home. The tile was finished a little less than a year ago and we moved into the house in December. Sometime during May or June the family stopped wearing slippers as the temperature became warmer. I immediately noticed that about 90% of the tile grout was not installed to the "leading edge" of the tile. These tiles have a fairly sharp leading edge which makes it uncomfortable and sometimes painful to step on most if not all of the joints with no shoes. I have contacted the tile store sales person who stated that they can grout over the existing grout and will work with the installer on scheduling a repair. I would say that on most of the floor, rerouting would add an 1/8 inch of grout, maybe a little more in a few isolated areas
ANSWER
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.
Using an epoxy grout can be applied at a much thinner application, but you would have to apply it over all of the grout so that it matches in appearance. Again the existing grout will have to be properly prepared to ensure an adequate bond.
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At this point, the tile and grout are about 1.5 years old. What would be the proper preparation to the existing grout to ensure adhesion for the new grout?
First you need to select the grout product you are going to use. E.g. cementitious or epoxy. Then get the grout manufacturer’s data sheet on recommended uses and limitations. Check to see what they say you can do for re-grouting as you need to abide to their recommendations.
Generally speaking you have to do a thorough cleaning of the grout. If there is a sealer on the grout you will have to strip it. You need a clear porous grout with enough depth so the grout will fill and stay in the joint and adequate bond to the existing grout and the edges of the tile that it comes into contact with.
I just bought a house and it was a flipped house and now finding the tile work was very poorly done. The grout at some if the spots are very shallow or nicks w missing grout this is an entire shower and floor. Can i just re grout the whole thing after cleaning the tile and grout? will the epoxy grout work better . Will there be a good bond?
Yes you can fill in those missing cementitious grout spots with new grout. Just dig it out completely in the area of repair and clean it before applying the new grout.
Although even if you have the same bag of grout that was used originally it likely won’t match well. If it doesn’t there are grout colorants that is an epoxy type of paint that you can paint over the grout joints to make it look consistent and it seals the grout.
You wouldn’t want to use epoxy grout unless the original grout is epoxy.
I’m asking the same question can I clean the shower and apply new grout over the old grout he depth is no problem the stones are really high, it’s will it adhere to the shower I’m concerned about.
You need to use a polymer modified grout that has a better bond strength. It is critical that the original grout is clean and you need at least 1/8″ depth to get the grout to stay in the joint.
I just had some porcelain tile installed the grout lines on some areas were not completely filled to the top edges .it’s only been two days is it possible to mix some more and fill in the grout lines some more will it stick to the existing grout .
You don’t want the grout flush with the edge of the tile or the grout will tend to get dirty easier and will be more difficult to keep clean. If the grout joint has a slight concave then it won’t tend to get as dirty.
Generally speaking if you try to apply a thin layer of grout over existing grout it will not blend in and will look like a patch. It would be better to grind the grout out and and re-grout if it is that bad.
I just had my bathroom remodeled with a brand new subway tile and mosaic floor. The contractor said I don’t need to seal the shower floor because it will be slippery. I’ve showered in there for about a month. Is it too late to seal it? Should I let it dry out for a few weeks first? What if we don’t seal it?
There use to be silicone sealers sold for tile, but they would make the floor tile surface too slippery. Today the penetrating sealers applied to tile will not make them slippery. In some cases it makes them more slip resistant.
Sealing is a temporary treatment. It has to be reapplied every 6 months to a year depending on how often the shower is used. If water doesn’t bead up and if water absorbs into the tile then it is time to reseal.
To seal the floor you need to make sure it is as clean as you want it to be, otherwise you are trapping stains in the tile. So first clean the tile. Let it fully dry for a day or so. The apply a tile sealer. For a porcelain mosaic floor the tile will not absorb much. So immediately after applying the sealer, buff it off with a dry lint free cloth. Go to our resources page to see some sealer options. https://ctasc.com/category/resources/cleaners-sealers/
my 20 yr old tile shower shows slimy white stuff running down on to the shower floor. Was not used in a long time. How to fix it?
It could be a microbial growth if it had been damp and not cleaned in awhile. If so can use bleach to clean it off.
It could be efflorescence which is normally a symptom of a moisture problem where it causes a calcium mineral migration through the grout. If so, you scrap off excess and use diluted vinegar or other acidic cleaner designed for removing efflorescence. If it is calcium if you scrap some off and put into vinegar it should effervesce (bubble).
I just re grouted my shower (new over old) as the grout was stained/missing in some places. (Just moved in and the place is about 39 years old) the missing grout wasn’t much. Just small sections here and there. I cleaned the grout and tiles well before starting. My question is how long I have to wait before I can seal?
Generally speaking after two or three days the grout should be dry enough to seal, but it depends on the type of sealer you are using. You should follow the directions of the sealer.
I bought new kitchen backsplash tile and grout. My installer had it up and grouped by the time I saw it; and the store sent me home with black carbon grout! It was supposed to be light light grey! Can I just do a skim coat of the light grey over top?
Applying a thin coat of the light grey grout will likely not turn out well. Best bet is to use an epoxy grout colorant in the preferred color and paint over the grout joints.
I have a beautiful backspash behind my stove made of stone with cement grout with a sealer on it. I would like to apply a fresh skim of cement grout to freshen up the cracked areas from installing a new kitchen and countertop. How would I go about doing that and what products would I use?
Applying a thin coat of grout will likely not turn out well. Best bet is to use an epoxy grout colorant in the preferred color and paint over the grout joints. Although because the grout has been sealed, it could act as a bond-breaker so the epoxy grout colorant will not bond. So do a test first to make sure it works.
I re-grouted my bathroom floor today. There are some areas where the grout is not level with the tile, basically the edge is noticeable when walking on.
Would I be able to fill these gaps without removing any of the new grout. We’re talking 12-24hours since I finished re-grouting
Probably not. The new grout would need to be about at least 1/8″ thick and it would have to be a polymer modified grout to bond to the existing grout and that might not work well depending on the condition of the existing grout. Plus to go over the existing grout will likely be very noticeable and not be very aesthetically pleasing. Whatever you do first test out an out of the way area to see if you are satisfied with the results before doing the rest of the areas.
Our bathroom is about 10yrs old and the custom shower having a natural river stone floor has a significant amount of grout missing. Would it be better to try and clean and remove more grout where it is still good to insure sufficient depth? Or, remove, reinstall the stone and regrout? The floor is approximately 20sqft, and because the stone is irregular I would not be looking forward to Dremeling out the irregular grout lines! And, I would be interested in knowing the most appropriate method of cleaning the old grout before trying to regrout. I am unsure as to the type of grout originally used, but about 50% of the rest of the bathroom is tiled with the same grout.
You should remove any unstable or loose grout. You can powerwash the tile floor or get a scrub brush with a detergent and scrub it down and let the detergent soak in for awhile and scrub again. Then thoroughly rinse the tile and grout. You can then fill those voids in the grout with new grout. Even if you knew which brand and color of grout used it isn’t likely to match well at first. Over time it might blend in. Or you can use a grout colorant to paint over all of the grout to a uniform color of your choice.
I have a 60 sqft bathroom tiled in 2”x2” tile. The tile is white as is the grout. The grout has become dingy on the path from the door to the toilet, the other areas are fine. I want the grout in this traffic area to be as clean as the other parts.
Can I simply clean the grout in this area and reseal? Or should I clean and regrout the entire floor? The existing grout is not exactly flush with the leading edge but close. Maybe 1/16” or so. So if I did regrout, I’d imagine I’d be using an epoxy.
You ought to clean and seal the entire bathroom floor. There should not be a need to regrout. It is good to have a slight recess in the grout joint so the foot traffic isn’t in direct contact with the grout. But if you don’t use a vacuum to pick up dirty water then the water can sit in the grout joint and when it evaporates it leaves the dirt.
Traffic paths will tend to collect and show dirt, but if you use a scrub brush on an extended handle with a cleaning solution and pick up the the dirty water with a wet vacuum it should keep the entire floor clean. The sealer will help keep the dirt from clinging to the grout and will make it easier to clean.
The house where I am living has tiled kitchen counter tops, but the grout does not come flush with the tile and debris is always getting stuck in there. I would like to regrout the counter so that the grout is flush with the tile. What is the best way to prepare the old grout for this?
To regrout the countertop you need to remove the grout with a grout saw. Clean it thoroughly to remove any contaminates and regrout. It is a tedious job and you could chip the tile edges during the process.
If there is at least 1/8″ depth in the joint by partially removing the grout, you can try to use an epoxy grout to grout over it. It is tedious process and you might chip the edges of the tile. You have to thoroughly clean the remaining grout to remove contaminates and to leave it dry. Applying the epoxy grout so thin can be difficult to get it to stay in the joints uniformly. Epoxy grout is a lot more expensive and more difficult to use and clean up.
The wall tiles in my shower need regrouting – there are little holes opened up in the old grout. I know I need to remove at least some of the old grout to yield a clean, porous surface. What is the best way to do that? Fortunately it’s plain white grout so should be easy to match if I don’t need to cover the whole area.
There are carbide hand grout saws that can be used for removing the grout, but you have to be careful not to chip the tile. You could just clean the surface, let it dry and if the pin holes are small you can fill them with a thin coat of caulking sealant. The white sealant might not stand out over a clean white grout or it might be noticeable. Experiment first to your satisfaction before proceeding.
Hey there. Very informative replies here. I have a mosaic tile shower floor in a mud set with sanded cement grout and a few cracks here and there with a couple of areas that stay wet longer making me think there’s some superficial failure of the grout-which probably hasn’t been sealed for years . There are multiple areas of grout discoloration and the grout is 2 mm + recessed below the mosaic tile in places, creating an irregular profile. I’m considering removing 4mm of grout as best I can and going over it with Spectralock premixed epoxy to hopefully extend the life of this shower floor. This will be a lot of work in this 4×6’ walk-in shower, but I’m up for it. There’s also an issue with failed grout where the floor meets the wall. Curious if you have general recommendations on the project and whether you would float the epoxy into the corner joints a bit, or save that entirely for tile caulk?
The grout shouldn’t crack if the tile installation was installed correctly.
It is not unusual for grout to become discolored over time. Normally the residuals from using the shower absorb in the water and the residual water that sits on the recessed grout evaporates and precipitates the dirt. To prevent this you need to use a liquid floor detergent in the water and apply to the floor and let it soak for 10 minutes. Then scrub with a scrub brush on an extended handle. You can pick the dirty water up with a wet vacuum or in a shower you can just wash the the dirty water down the drain.
All transition joints from floor to wall or wall to wall or at any change of plane should be filled with an ASTM C920 sealant that is normally silicone or polyurethane. Those joints need to be resilient to mitigate movement.
Hi I just had my kitchen splash back tiled but find the grey grout a little to dark can I grout a lighter codour over it or paint it a lighter color?
Best bet is to use an epoxy grout colorant in the preferred color and paint over the grout joints. You can paint a light color colorant over a dark grout. You can buy this product to match grout colors. Just go to your local tile distributor to purchase the grout colorant.
Hi
I have exactly the same problem, it looks so harsh. Did you change it or learn to live with it?
Hi! I just had a contractor install light gray stone tile and attempted to purchase a similar gray toned poly grout. my order was messed up and they gave me a sandy tan grout that looks awful I was not home at the time so when I arrived home I was shocked to see the color and my contractor had already left no fault of his he was not aware of my color selection. It was done roughly 12 hours ago. what is the best thing to do here? I want the correct grout color used and am willing to have it corrected but am not sure what to do
If the grout was only installed 12 hours ago you should be able to dig it out without too much effort. Of course that takes time and you could chip the edges of tiles if you are not careful.
Or you can use an epoxy grout colorant in the preferred color and paint over the grout joints after the grout has dried. Make sure the grout is clean before applying the colorant.
Hello, I am trying to regrout my 34x34in shower tiled with 12x12in tiles. The shower room has been cleaned and left unused for about 3 months. The shower is about 10 years old, Today, I removed the old grout and found a little water patches underneath. Not all areas just 3 or4 places between half an inch wide to an inch. I have removed 2mm or 3 mm deep and the tile is 10mm deep. Do you think I should get the professional and remove the tiles and repair it in case water under the tiles? How do I check to be sure of the water damages? Please help.Thanks
It is normal for water to saturate the cementitious grout joints. Sometimes the installers leave voids in the adhesive behind the tile that can collect water. This won’t hurt anything as long as the substrate is properly waterproofed. Sometimes this condition can cause white efflorescence deposits to collect on the grout joint surface. If there are any loose tiles or if the substrate seems to have gotten wet and gotten into the wall cavity then you do need to remove some tiles to determine the problem and to determine if you can repair it or if you need to replace the entire shower.
Hi Donato…
I don’t imagine this string is still alive but you’ve been incredibly helpful. Hoping to get another question answered quickly as I’m in the middle of running down an issue. I started what I thought would be a quick repair on my shower floor (about 5 years old). I’ve grinder out the grout on the entire floor about 1/16-1/8 of an inch but there are areas that seem to have moisture that were effecting the surface color when I surface grouted. I redid the entire process of digging the grout out but I’ve been more aggressive with the damp areas (trying to get to the bottom of the damage. I’ve grinder just about to the bottom of the tiles in the damp areas but it all still appears damp. If I regroup over it, will the discoloration make it to the surface? Thanks in advance!
If there is moisture migrating through the tile from beneath the tile, then regrouting won’t make it go away. Even if you grout with a silicone or polyurethane sealant or with an impervious epoxy grout, the water can still migrate through the tile. So you might be able to stop the moisture from migrating into the grout, but that probably will not remove the decolorated surface.
You can try sealing the tile with a penetrating sealer, but it doesn’t make the tile waterproof and only makes it temporarily moisture resistant. So you can try this and then reapply as necessary.
Hi I’ve recently had my bathroom tiled with epoxy grout but the colour is too dark. Please could you advise of the best way to lighten this? The tiles are on the walls only. Many thanks
You can’t grout over the existing epoxy grout. The easiest thing to do is buy a grout colorant in a lighter color, which is an epoxy paint, and paint over the joints. It is a tedious process, but if you are careful it can give you the color of grout joints that you want.
I have a bathroom with a decorative tile on the walls, it is not in contact with any water.
I used a recommended epoxy all in one grout / sealer. but after the first 6 moths the white grout is turning yellow. and stains are appearing. my question is can i grout over it with a non epoxy grout? I’m afraid if i use another epoxy it will stain as well?
If the grout is a true epoxy, I would review the manufacturer’s data sheet and see if they say their white epoxy grout does not yellow. Over the years white epoxy grouts do have a tendency to yellow for a number of reasons. If the manufacturer says it doesn’t yellow then you should file a claim with them.
You can’t grout over the existing epoxy grout. The easiest thing to do is buy a white grout colorant, which is an epoxy paint, and paint over the joints. It is a tedious process, but if you are careful it can give you the white grout joints that you want.
I just had my bathrooms redone with a porcelain tile. The contractor picked the grout which is a sanded grout, the grout lines are too heavy in some areas and not clean lines. How can I safely straighten the lines and remove excess grout on the tile? Additionally, , when it gets wet it almost turns black and takes hours to dry and lighten back up. Is sanded grout the right kind to use in a shower and how do I properly seal to protect from water damage without making it darker?
Sounds like the installer didn’t do a good job at grouting. The grout joints should be consistent and true per the standards. The only way to adjust the joints is to try to carefully chisel or grind away the wide areas without chipping the tile. It may affect the appearance of the grout depending on how it is done.
Sanded grout has greater strength and shrinks less than non-sanded grout. You can use a sanded or non-sanded grout for grout joints that are 1/8″ wide, but if they are less than 1/8″ wide you have to use unsanded grout so it fits in the grout joint. Grout joints over 1/8″ wide must use sanded grout to avoid cracking from excessive shrinkage.
If you seal the grout with a tile and grout penetrating sealer it should prevent the grout from turning dark as long as the grout isn’t submerged. The grout has to be thoroughly dry before applying the sealer. Follow the sealer manufacturer’s directions. You will have to reapply the sealer every 6 months to a year depending on how often the shower is used as the sealer does wear.
Water doesn’t harm the cementitious grout, in fact, the cementitious grout gets harder and more dense over time when subjected to moisture after it has cured. You
Hi, just had glazed porcelain kitchen wall tiles installed, about 4 sq meters. The grout was put in less than 24 hrs ago. Granite grey color. After cleaning phase it looked like a few lines were low. The grout was lighter in color and I could see the white c2 class til adhesive almost showing through. Tried to level it with some leftover grout. Forgot that a little water was added to the leftover grout to make it less thick. The added patches were even more lighter in color. Which made the problem worse. Can remove these areas with a screwdriver. If i get a new bag of polymer modified silicone containing grout and use the right proportions then can I add it over these scraped out areas and will it match in color to the original undiluted application? I must wait 1 or 2 weeks to do this. Can this delay cause other issues? Thanks for the site.
Generally speaking, if you take the same cementitious grout from the same bag that you did the original installation and then later patched the grout it will look different and show.
Generally speaking, cementitious grouts will tend to dry a different color based on high fast or how slow it dries. If you are going to try to patch it, it probably would be better to do it sooner while it is still curing..
Little update. Opened a new bag, same color and brand. By the way it is a polymer modified grout. Anyway what I see is that the areas where i cleaned out the old grout turned out better. The spots with the old grout was slightly noticeable. But its not so bad. Overall glad that i redid those spots. Highly agree with cleaning out the old grout as much as possible. Thanks again for answering my posts and for the awesome website. Have another questio about “technical porcelain full lapato” tile. The guy at the hardware store said it was good for the bathroom floor. Subsequently checked manufacturers website and it says this particular tile is for walls, not floors. Anyway ended up using it outside on a few balcony steps entryway. Not too worried about it, got the tile cheap on sale. And it is mostly for show. Using a seperate balcony entrance with old granite tiles. Wondering if you could comment any thoughts about “technical porcelain full lappato” btw I am living overseas. Thanks again!
Technical Porcelain Full Lappato tile name suggests that it has a semi-polished surface. Porcelanosa’s Urbatek technical porcelain tile is a throughbody (unglazed) porcelain tile with an absorption of less than 0.1%. They suggest it is suitable for interior and exterior applications.
Bottom line is believe the manufacturer of the tile’s recommended usage and not the guy at the hardware store.
So I really want to do a gold/metallic grout in
My bathroom. This is purely aesthetic. Can I just do a new light coat of grout over the existing grout to make this happen? Or is there some sort of glitter/metallic paint I can put over the existing grout?
Normally you need to grind down the grout to allow at least 1/8″ depth to be able to put grout on top of it and it needs to be a polymer modified grout or an epoxy grout. Laticrete has an epoxy grout called Spectralock Dazzle that comes in metallic colors I think that it glows in the dark.
There are epoxy grout colorants that you can paint on to existing grout, but I haven’t noticed whether they have metallic colors.
Hi, contractor used darker colour than I was hoping for in new shower tile, it’s been barely used for shower at this point over few months. About to re-do bathroom vanity backsplash to match and wondering if I can lighten the shower tile or I’m stuck with matching backsplash to something I don’t want? This is product: https://www.lowes.com/pd/MAPEI-Ultracolor-Plus-FA-10-lb-Warm-Gray-All-in-One-Grout/1000057513
The grout manufacturers offer epoxy grout colorants that allow you to paint over an existing grout color to change the color to a different grout color. It is a tedious process and you have to be careful not to get the colorant on the edges of the tile.
I put down my 17″ tile on my dining room floor ( I’m a novice) the grout I put down was Mapei Flexcolor 3d Ready to Use about 6 months ago. I did not put down enough grout, We still have plenty left. Its about an 1/8″ short all over. Could I put down another layer over that one?
First you need to verify with the manufacturer Mapei to see if they say you can apply an additional 1/8″ layer of the grout over the existing grout. They should know if that will be problematic or not.
Generally speaking if you have 1/8″ depth you can apply an epoxy grout over it and in some cases a latex or polymer modified cementitious grout over it.
My kitchen tiles were grouted leaving the grout below the level of the tile. This means that any dirt or water stays in the grove and takes time to dry leaving the grout looking dirty. After cleaning out the grove, can I use a light solution of PVA in the grove, allow to dry and then re-gout. the gap is about 2mm between the tiles
Normally you need about 1/8″ depth to be able to grout over existing grout. Applying what we call a slurry bond coat over the clean existing grout can help. You could paint on a latex as a primer to help facilitate a bond, but you still need some depth.
PVA glues (polyvinyl acetate) are not very water resistant so you would be better off using a CPA glue (concrete plaster adhesive) or an acrylic latex as your slurry bond coat.
I have a small area of one year old sanded Polyblend shower wall grout that was darkened from rust coming from the hardware behind a grab bar. I tried cleaning the grout with an acid cleaner and it had no affect. Can I assume that the grout was not sealed by the installer and, if so, can I put a thin layer of grout over the darkened grout?
Sealing grout is only a temporary process and it won’t prevent hardware from rusting and bleeding into the grout.
I would cut out the grout in that area and the fill it with an ASTM C920 sealant such as a 100% silicone sealant. It might keep the rust from migrating into the grout. But what you should also do is remove the grab bar and reinstall with stainless steel hardware otherwise it will continue to rust.
l had additional grout added to existing. The shower was used about 6 times. I wiped he tile with a damp cloth from a bucket of warm water and Dawn Detergent. I made sure the cloth was just damp enough to remove any soap on the tile. the grouter arrived 4 hours later and regrouted on top of existing grout. Some of the grout is Bright White, as it should be, some now is medium gray. The company is saying that it’s because i wiped the tile and it’s my fault. Is it? They say it has to cure. It looks the exact same as the minute he had finished. I pointed the darkness out to him immediately. Thank you for your time in responding and advising.
Could there be another reason? Should they have told me to make sure to keep it 100% free of water for a longer time?
First of all, cementitious grout is sensitive and depending on how fast or slow it dries the color can vary. Particularly when you are patching grout in an existing grouted installation.
If for some reason some of the grout they were installing over was more absorbing that other portions then that are would dry faster that then could the color to vary.
Grouting over grout isn’t a normal process and there is no standards addressing that process.
Normally the grout color will have a dark look when first applied and will lighten some as it cures and dries.
If color variation is too extreme for you then you can buy a grout colorant that is basically an epoxy paint and paint over it with the color you desire. It is a tedious process, but it is an option.
I am would like to create a slight german schmear affect using Capella Porcelain Bricks 2×10 in a herringbone pattern. What kind of grout should i use and will this even work?
The German Schmear technique is akin to whitewashing bricks, but instead of using diluted latex paint, homeowners coat the brick with a layer of wet mortar. … It also gives the bricks partial coverage, which softens the harsh straight lines that exist in traditional brick siding and creates an irregular pattern.
The point of using this method versus paint is that the mortar won’t penetrate as deep into the brick as paint would. No grout manufacturer would recommend their grout for this application since it isn’t common nor an application that grout is made for.
I suggest you experiment and test to verify what works the best for you. You can create small sample boards by bonding the tile to a cementitious backer board and after it cures grout it. I would tend to go with a polymer modified cementitious grout that will bond better to the brick. You can try different colors to see what looks the best. Not sure how well it will wear, but I wouldn’t expect it to wear well under foot traffic.
I had new porcelain encaustic tiles laid in my bathroom about 2 weeks ago. The flooring subcontractor said he was going to use 1/8inch spacing so he used Mapei unsanded grout. His spacing was actually 1/4in so the next day I saw pinholes in various places in the grout, some cracks, and when the grout dried the color was uneven. The general contractor said they would send someone else to address it. He was not able to come right way. He suggested putting sanded grout but said he would not have to remove the old grout. Is this correct? The grout has not been sealed, but is a few weeks old. Does the old grout have to be dug out to a certain depth before the new sanded grout can be properly applied?
The manufacturers of non-sanded grout say do not install in grout joints wider than 1/8″. That is because it will tend to crack.
The cracked non-sanded grout is cracked so if you install grout over it then it is likely to crack.
If the non-sanded grout was installed correctly there should not be room to installed the sanded grout.
If the existing non-sanded grout has been sealed then the sealer will tend to act as a bond breaker as it doesn’t allow the absorption or mechanical attachment to the existing grout.
All of the grout should be removed and replaced with a sanded grout. They have to do this carefully or they will tend to chip the edges of the tile. So you need to watch them closely. Considering what they told you, you might not be able to rely on them to do the regrouting correctly.
I have a very old tiled kitchen counter where cement grout was used. The grout crumbles and chips whenever I scrub it so it’s impossible to thoroughly clean or keep debris out of the cracks. Is there any way to fix this issue without taking out the counter or tiles? (It’s a rental property.)
If the grout is that fragile, you should remove the grout and re-grout it. There are grout hand saws, but the grout joint needs to be at least 1/8″ wide to use it. If you have a tight 1/16″ grout joint and if the grout is that unstable you probably can use an utility knife to remove the grout. Be careful to not chip the edge of the tiles. Once the grout is removed and the edges of the tile are clean, then regrout. If the grout joint is less than 1/8″ wide then use a non-sanded grout. If the grout joint is 1/8″ or wider then use a sanded grout. Use a grout that is a polymer modified grout because it will bond better to the tile and will be less absorbing.
We have brick backsplash and the contractor who installed it did a more thin, recessed look with the grout. I want something thick and chunky looking for the brick. Is there a product that could be used to help fresh grout bond over the top of the first thin layer he did? Or what would you recommend? Removing all the grout from out backsplash and fireplace is out of the question. Would like to just regrout over the top.
Normally you need at least 1/8″ depth to grout over an existing grout. The existing grout has to be clean and absorbent. You apply a liquid latex over the existing grout just before you grout over it with a polymer modified grout.
Experiment first to make sure it will work the way you want it to.
Hi Donato. This may seem a strange problem, but I don’t know what to do. My bathroom’s [new-ish] wall tiles are a lovely aqua color, however they left the floor tiles which are also an aqua color, but nothing like the wall tiles. Hence we call the bathroom the ‘ swimming pool’. Also, the floor tiles are laid on a thick ?cement? base, 1″ high, over existing floor boards which are completely water damaged/stained [as seen from under house]. So the bathroom floor is 1″ higher than the rest of house’s timber floors. Therefore cannot use vinyl floor boards. Nor can I ’tile paint’ them, because there seems no product recommended for floor tiles. SO, my questions are [1] can the floor tiles be removed from the cement base reasonably easily and replaced? [2] Can I raise the grout level to the tile top [then sand until completely even/smooth, AND then lay vinyl floor sheeting over the lot? Hope you can advise me. Thank you, Pat ♥
Depending on how well the tiles are bonded to the mortar bed substrate and how carefully you remove them will depend on whether you can reuse the mortar bed surface. Generally speaking you can remove the tiles but then you have to use a patching mortar to fill in the divots caused by the removal.
If the tile substrate is structurally sound you can grind the surface and then use a patching mortar over it and the grout joints to create a flat surface. You can install vinyl as a cheap fix, but it will not last or perform as well as a ceramic porcelain tile.
If you have water damage on the wood floor boards then you might have a leak going on so you should investigate that to either determine if there is a leak and if there is to determine how to remediate it.
Hi, I’m re-grouting my bathroom floor. I’ve decided not to remove all of the grout but I am removing enough where I would be applying at least a 1/4” of new grout (many of the joints were low and uneven). I’ll make sure the entire old tile floor has been gone over leaving clean grout for the new grout to adhere to. I’ve picked out a polymer based grout to place on top. My question, is how long do I have to wait until I can use the shower? It’s my only Full bathroom and manufacturer is only giving a time based on if I was applying all new grout to a new tile floor.
You should always follow the grout manufacturer’s directions. There are some cementitious grouts that only require 24 hour curing like Mapei Keracolor S grout. Some want you to wait a week or so. Grout over an existing grout will probably dry faster, but there is no exact formula to determine how soon you can subject it to use.
Hi! I accidentally damaged the grout surrounding a tile (13.5” square) by using a harsh cleaner. It is pitted but not crumbling in some areas. Do I have to dig it out and regrout or can I grout on top? It is at least 1/8 inch in the damaged areas. Thank you.
I would buy a grout hand saw and abrade away any loose unstable material. If you have at least 1/8″ depth to fill you can clean the grout and apply a polymer modified grout over it if it is done correctly. Test it out in one out of the way spot to make sure you are satisfied with it before doing it all.
If you are only doing a portion of the grout then the new grout will look different from the original grout at least for the first few months. So you might get a patched look.
Can we use normal cement grout over the improperly filled epoxy grout.
No you cannot apply a cementitous grout over an epoxy grout as it will not bond to it. If the grout joints are too low, you would have to make sure the epoxy grout joints are clean and it is deep enough for the epoxy grout to attach to the existing epoxy grout. You might need to cut out the existing grout and regrout with epoxy or cementitous grout.
Hi Donato,
I have a shower floor with 1″ circular tiles, the kind that come on a mesh fabric.
I realize now that I used too much thinset and in places it squeezed up between the tiles, leaving virtually no room for grout.
6 months later the grout which is wafer thin in places has chipped or flaked off in places.
There is a musty smell.
So it is a mess.
I am considering tiling over the whole thing – is that possible?
The tiles are not loose but I worry about moisture under the tiles. Is that where the musty smell is coming from?
What are your thoughts,
Thanks!
You should have removed the thin-set from the grout joints while it was fresh prior to grouting. If the grout is applied too thin, it would adhere well.
The musky smell is normally because the waterproofing in the shower pan wasn’t done correctly. If either there wasn’t a proper slope of 1/4″ per foot towards the drain at the waterproof membrane then water can be trapped. Also if the weep holes of the lower part of the drain are plugged then water is trapped again and the underlying showerpan never dries and can develop microbial growth that can cause a musky odor. The only way to find out for sure is to remove the tile and mortar bed around the drain an at the wall to check for slope and to see if the weep holes are open.
You can tile over if it is scarified and cleaned and you use the proper polymer modified thin-set mortar adhesive. But that won’t fix the musky odor of the waterproof problem if in fact you do have those problems.
Donato,
Just happened to run across your web site. Found it very interesting. There is one thing I found very puzzling, and that pertains to re-tiling over old sound tile. I see no mention of using Silacone Adhesive/caulking instead of thin set. I was a commercial sign contractor for many years and we often used decorative tile accents . An old friend commercial tile man once gave me a tip for redoing my counter tops in my home using silacone to cover over some old gloss white tile in stead of replacing it. Worked like a charm. Five or six dollops on the back of the tile, press into place grout with polymer grout next day, magic. Used the process on any and all sub surfaces, never a problem. Ended up tiling over all the tile in my home, floors, walls, showers, entry, fireplaces and exterior barbecue. Some of it has been in place for more than twenty years. Looks great
Chuck Ropuse
Silicone sealants that meet ASTM C920 do bond to tile very well. The reason it isn’t recommended for bonding tile to any surface is because it is compressible and because you can’t practicably meet the required standard of achieving 80% contact between the tile and its substrate for interior applications nor can it practically meet the standard of achieving 95% contact for interior wet areas or exterior applications.
By having excessive voids under the tile it makes the tile more vulnerable to cracking and crushing when subject to heavy loads, and for exterior wall applications it is more prone to get excessive efflorescence staining.
If you could achieve the 80% or 90% coverage with no voids larger than 2 square inches (size of a golf ball), I would be concern that the sealant is compressible that would make it susceptible to movement damages.
ASTM C920 Sealants are great for movement joints and for grout joints.
We had new house built about 3.5 years ago and have porcelain tiles in mud room/laundry room off garage and right by the garage door. Now the tiles are coming loose (grout coming out in chunks and can hear the difference when dog nails hit these tiles as they almost sound hollow). Can I just re-grout or do the tiles have to come up and get reinstalled?
The the tiles are loose, sounding hollow and the grout is coming out that would suggest that the tiles have become debonded to some degree. Replacing the grout will not solve the problem. You likely need to replace the tiles.
To determine the cause of the problem so you can avoid it reoccurring, you need to remove a couple of tiles in different conditions to look for evidence of why it failed. If all the thin-set adhesive stayed bonded to the back of the tile and came of cleanly from the concrete substrate, then likely there is a bond breaker contaminate on the concrete. So it would need to be scarified before you re-install tiles. If the thin-set came off cleaning from the back of the tile and stayed bonded to the substrate, then maybe the back of the tile has a contaminate or maybe the installer did not key the adhesive into the back of the tile as he should have.
Maybe you don’t have any resilient movements at the perimeter of the walls and that is a contributing factor.
Generally speaking, when there is a failure it is never due to one single deficiency but rather due to multiple compounding deficiencies.
Can I add an Epoxy over my brand new unsanded bostick Grout? My contractor just put in my kitchen backsplash and it looks flawless–I’d love to preserve that and it occurred to me that epoxy over the grout might be an option? Would you agree? If so, what clear epoxy product might you recommend? Thank you in advance for any guidance-your site and expertise rock.
Clear epoxies tend to yellow over time so it would not be recommended to apply it over your grout. Plus it would change the appearance of the grout.
If you like how your grout looks then seal it with a penetrating sealer like Miracle 511 Impregnator. It doesn’t last forever, but for a back splash it should suffice.
Thank you so much for taking the time to respond and share your wisdom!
Hi, I read through the comments. I see that you recommend epoxy colorant to change the grout color, but you do not recommend putting epoxy over sanded grout. I grouted my shower tile with SimpleGrout Delorean Gray about 2-3 weeks ago. I would like to darken the color. I am not a professional and only did this myself because I couldn’t find anyone to hire during COVID. Please let me know if there is a DIY solution or if I have to live with this color. Thank you for your advice.
Grout colorant is an epoxy paint for changing the color. Epoxy grout is material that requires at least 1/8″ depth to apply over a cementitious grout.
If you like the color but want it darker e.g. more of a wet look, you can apply a sealer enhancer over the grout. Be sure to test out whichever method you choose to make sure it will meet your satisfaction.
We have a small shower that has a pebble stone floor. When installed a couple years back, the contractor used TEC Power Grout which is a cement-based grout. Unfortunately, the grout is too low and causes water to pool which turns into mold/mildew.
Last weekend, we thoroughly cleaned the shower with bleach and let it dry. We then added a thin layer of the same Power Grout to bring the level up. After drying for 3 days, my wife took a shower and noticed the grout was flaking up everywhere.
At this point, what is the best way to resolve this? I cannot imagine scraping up all the grout to get to a 1/8″ depth around all the pebble stones. Should we scrape up what is loose, prep/clean the shower, and then use a thin coat of epoxy grout over this?
Even with a thin layer of epoxy grout it will be difficult to keep it in the joint in a uniform manner during the application process, but once it cures it should stay.
We accidentally mixed grout with well water and it dried inconsistently in color with the white residue coming through. The tiles are 2inch hexagons in the bathroom so the idea of scraping out and regrouting is daunting. Any quick fixes?? We tried an acid cleaner but no luck. We haven’t sealed it yet.
If the grout is blotchy you can coat the grout with an epoxy grout colorant. They are made to match most grout colors produced by the various grout manufacturers. Although you will get a uniform color it does have a bit of a sheen.
It is a tedious process to paint all of the grout joints with this epoxy grout colorant paint to keep in straight and off of the tile. You need to tape the tile edges with painter’s tape, which on a 2″ hexagon that is a lot of work.
Oh boy. Any other less than ideal fixes? That sounds way too time intensive- we have a baby on the way and a toddler. Please say there is another option…?
we only recommend doing things correctly, which typically is never easy…
I am planning on putting some peel and stick floor tiles down. Currently the floor has 15cm tiles down. Will I need to raise the grout lines so they do not show through? Is so what’s best to use?
I assume you are thinking about installing LVT tiles or something like that. You would need a flat surface. You need to possibly scarify the surface of your existing tile or at least deep clean and dry it. There are self leveling mortars that be can applied relatively thin to go over the existing surface assuming it is structural sound. Some thin-set mortars are recommended for tile over tile applications without scarifying. You could skim coat over the tile surface with that product. Make sure you follow the manufacturers directions both for the LVT and the mortar.
By the way, LVT is often sold as being waterproof which is misleading. The product itself maybe waterproof, but it doesn’t make the floor waterproof after you install it.
I am patching grout in very old, well-maintained shower with Polyblend grout. I have dug out grout where a bit loose, but most of the grout is fine. I need the Polyblend to adhere to the existing grout. Do I need to moisten the existing grout or put any other substance on it to help the new grout adhere? Also, I have a container of a grout/adhesive from a big box store that I could use but hesitate because I read it leaves pinholes. Should I use that as it would be easier to apply? Thank you for your help.
Make the depth of removed joint as deep as possible so the grout will be lodged in. If the depth is too thin it will be hard to keep it in during the installation. You need to clean the grout and rinse it so there are not residuals from cleaning. Let it dry, but it can remain damp when you install it. Do not use too much water during mixing and cleaning or it will weaken it. Let the grout set up for 15 minutes or so before cleaning it, but scrap off any excess grout right away.
Hello,
The contractor just installed a tile shower floor. We used an all in one grout that states it does not require a sealer. 1/8” spacing.
The top of the tile is glass and bottom appears to be a synthetic stone/porcelain of some sort (cannot really tell). There are a few (not many) small pinholes after the first round of grout. It has not been sealed yet and grout states it does not have to be sealed (but sealing is OK per manufacturer if desired).
Question is if we should seal with a penetrating sealer or use and epoxy paint (this will change color which is OK). Goal is to last long and look appealing).
Thanks for any expertise you can provide!
If you put a drop of water on the grout and if it doesn’t absorb into the grout, which means it should not leave a dark/wet spot on the grout after you wipe off the drop of water, then you don’t need to seal the grout.
Sealing the grout can help prevent grout staining, and it can help make it easier to clean the grout as various materials won’t tend to stick to it.
If you do seal the grout, and you are willing to keep the same color, then I would use a penetrating sealer to seal the grout and glass tile. The glass tile is impervious so it really doesn’t absorb, but it is easier to seal the entire floor than to try to just seal the grout. The sealer on the tile will help keep things from sticking to it.
You must clean the tile and grout first and once it is dry then apply the sealer. After you apply the sealer you have to use a dry lint free cloth to buff it dry right after applying the sealer or if it is left on it can get tacky and be a maintenance problem. Sealers don’t last that long. You might need to seal every year or more. If water beads up and doesn’t absorb into the grout it is working. If not, it is time to reseal.
If you use an epoxy grout colorant it is a tedious process to dry to keep it only on the grout, and it could wear over time.
Hello. I recently had a porcelain tile floor installed and the contractor used a non cement grout. The grout was left unsealed for about three weeks and the grout turned white. It was originally a dark gray and I was told once they sealed it and it dried completely, it would turn back to the dark gray, but it did not. Why did the grout turn white and how can this be fixed? The floor is about a month old. Thank you for your time.
A non-cement grout is normally an epoxy grout or a urethane grout and they are normally impervious grouts. So I am not sure what kind of grout it was that got installed in your tile.
Normally when cementitious grouts are over watered in mixing it or the installer used too much water when cleaning the fresh grout off of the floor they can pull out the pigments in the grout that can cause it to lighten up or get blotchy. Best bet is to find out who is the manufacturer of the grout and contact their technical service department to find out what might have caused it and how to fix it.
Our contractor just grouted our kitchen tiles yesterday. Looking at it this morning we see several places where the grout didn’t fully fit between tiles. In some places it is fully up to the level of the tiles, but in other places there are gaps where the grout level is very low between tiles. My wife is freaking out! When the contractor comes today it will have been 24 hours since the grout was laid. Can they add more grout in those places? If they won’t do it, can we? Thanks for sharing your advice!
The grout should fully fill the grout joint from top to bottom without voids.
The grout normally should finish at the bottom of the relief edge of the tile. Normally there is a slight chamfer edge. You don’t want the grout flush with the surface of the tile so shoes make direct contact to it if you can avoid it, as it will tend to have the grout get dirty faster.
They might have to remove some grout to fill the grout joint full and so it doesn’t standout. Normally when you fill a hole in the grout, depending on the size, it will tend to look different.
hi there, my kitchen floor is about 2 years old and was installed by someone who isnt very good at tiling. the grout has been cracking and small areas falling out most likely due to slight movement from either the 50 year old framing or the ditra-heat system underneath not being installed correctly. unfortunately the tile floor runs underneath all the cabinets, appliances and kitchen island and would cost way too much to tear out and redo.
My question is can I simply cut out some of the cementious grout atleast 1/8″ deep and re-grout overtop the cementious grout that’s left with an acrylic or epoxy grout that is more flexible so it wont crack and fall out again? TIA
The symptom of your problem is the grout is cracking and coming loose, so you are suggesting that you want to treat the symptom rather than determining the underlying problem that is causing the crack to crack.
Normally if grout cracks it is due to movement and/or it could be the installer did not fill and compact the grout joints properly and/or didn’t mix the grout properly. If the tiles do not feel loose or show any signs of movement they may be stable.
The movement could be because the floor has too much deflection. If that is the case and you can access the underlying floor joists you can add bracing to stiffen the floor.
You can grout over grout as long as there it enough depth for the grout to hold in the joint. If you don’t fix the problem the cementitious grout may crack again. If you use an epoxy grout it is much more stronger and flexible so that may or may not work. You could install an ASTM C920 traffic grade sealant caulking that is either 100% silicone or polyurethane. It is very resilient and bonds very well. Although you have to keep the joint slightly recess so shoes doesn’t come into contact with it that could make it look dirty.
Whatever you do, test out a small out of the way area to make sure you are satisfied with the result you will get.
Hi Donato, our contractor installed sliced marble pebble mosaic tile on our shower floor. Grout wasn’t applied evenly and there are divots. Grout hasn’t been sealed. It’s been about 4-5 weeks since install – how can we fill the divots? Can a new layer of grout be applied or must some grout around the divots be removed? Thanks so much!
If there are divots (low spots) you can take the same grout and try to fill them; particularly if it is an ANSI A118.7 High Performance grout. Even if you have the same grout bag and use that grout the patched grout will likely be darker in color because there is less volume and it dries faster. Over time grout tends to get dirty and it all looks the same.
Patching the grout might look worst than leaving the divots. You should test out your repair methods first to make sure you will be satisfied with the outcome.
Help! Previous homeowner was a sloppy DIYer. The shower is completely grouted (no caulk) and the grout runs about 1/2” beyond each side of actual grout line on the walls and corners. In some corners it is discolored and weird looking. How do I DYI a fix? Can I just dig out the grout where I think the grout line is and refill that groove with an epoxy grout (have no idea what existing grout is —some type of sanded). Thank you!
Depending on the type of tile and how well the grout is bonded to the tile surface you may or may be able to remove the grout without damaging the tile surface.
You have to experiment. I should get grout saw first cut out the grout. Then get a metal scraper and try to carefully scrape of the grout from the tile surface. Test it out first to make sure it will work to your satisfaction. After you remove the grout and clean the joint, you can regrout it. There are some good pre-mixed grouts that you can use to regrout that will make it easier.
Kudos for answering questions long after the article was posted! I’m curious about possible temporary stop-gap solutions for old grout that is absorbing fluids. It’s going to be a few months before we can cordon off the entire area for the couple of days it’s going to take to properly redo the entire floor, but we are able to block off small sections at a time. I have no idea what the current grout is, it has a gritty texture and porous appearance and darkens significantly when wet. Perfect color match doesn’t matter since this is a short term fix, the priority is reducing the absorbance as it’s prone to frequent spills. The repeated agressive cleaning to remediate lingering ordors from the spilled liquids are hastening the demise of the grout, and we’re at our wits end.
We’ve tried penetrating sealant, but its useless for spots with hairline cracks, and even after multiple coats where it’s intact, water will only momentarily bead, if at all, before soaking in.
If we put premix grout over the existing, how long might it hold up? The existing grout is pretty sunken in, so there is 1/8″ in many places, but the tile edges aren’t exposed.
It’s been half-jokingly proposed that we slap a thick coat of high gloss paint over the joints, and having spent the last several hours on my knees scrubbing an area that still smells foul, I’m now seriously considering it!
It doesn’t sound like there’s any sort of top coating that is viscous enough to quench the thirst of our sponge-like grout… But perhaps you could advise on what materials are certain to fail, so that we might experiment in hopes of a temporary solution?
Thank you for your time and consideration, and for the great content on your web page!
Best performing grout is an epoxy grout. If you have at least 1/8″ depth you in theory can go over it with the epoxy, but it requires more effort and expertise in working with epoxies. You also have to make sure the existing grout is stable and clean.
Hi! This thread is amazing. I have just had a tiler Install 2″ penny rounds and grouted them today. The grout job isn’t great (I prefer to tile myself so I can be as perfectionistic as I like!). sadly, there are low spots, there are marks, some grout on top of tiles, and some paper towel bits stuck in the grout! The GC hired him so I assumed he was professional.
In any case, the first grout, which was completed perhaps 6 hours ago, is a high performance polymer sanded as some of the grout in the shower wall between the rounds is as much as 1/4″. The proposed solution is to regrout tomorrow (within 24 hours) with unsanded grout. Will this work? Some areas are low, with edge revealed, some areas ok, so not full 1/8″ depth.
The fact they didn’t grout it properly in the first place would make me uneasy about them coming up with some unconventional method of grouting over the existing grout.
The new grout should be hard by the next day, so that won’t help much. It isn’t easy to grout with only 1/8″ depth let alone less than that.
Time will tell… good luck.
Hi. I have issues with my grout in the shower. 1st, the grout turns chocolate dark when it’s wet, but once it dries, it becomes a light beige color, almost bone color. Is that normal ?
2nd, the corners and bottom edges started to crack (i guess normal movement of tiles/floor/walls). so a year ago, I got some textured sanded grout caulking and caulked all around the corners. The issue is that after a year, i have lots of molded/mildewed areas. Why and how can i fix this permenantly ? I was thinking about removing the old sanded caulking and replacing it with unsanded caulking .
3rd, is it normal that when the shower gets wet, the regular grout turns the chocolate color but my sanded grout remains beige ?
Thanks for any input and directions.
It is normal for a porous cementitious grout to turn dark when it is wet and absorbs moisture. You can seal the grout with a penetrating sealer so that water beads off of the grout and it won’t turn dark. Although sealers don’t last so you have to reapply every so often depending on how much use the shower gets.
I assume when you say the corners and bottom edges are cracking you are referring to the grout joints that you then removed and filled with the sanded caulking.
Sanded caulking is normally an latex based sealant and not a quality long lasting material that meets the industry standards. The proper type of sealant/caulking is an ASTM C920 sealant that is normally either a 100% silicone or a polyurethane sealant. These types of sealants work much better and last much longer.
I assume when you said sanded grout you are referring to the caulking, which doesn’t absorb moisture so it would not change color when wet.
We recently had our tub walls tiled. At the last minute our tiler sent me to Home Depot for grout because he didn’t know what color white I would want. I had purchased the grout for the floor tile from a tile store but had to wait for delivery, so HD seemed the only option. Bother grouts were Mapei unsanded. The floor grout feels smooth, as expected. But the wall grout feels gritty, almost like a sanded grout, though not quite. I suspect Mapei is selling an inferior product through HD. My tile says he’ll apply a sealant, but I’m wondering whether that will do anything to smooth out the roughness (at least a little), or if there’s anything else I could try, short of digging it out and re-grouting . From reading your prior posts, it sounds like epoxy grout might just peel off since there’s not an eighth inch depth to fill. But I was hoping it might adhere OK to the rough, unsealed surface.
The good news is that it’s a guest bath that will almost never be used for showering, so will vary rarely need cleaning.
For grout joints that are 1/8″ wide or wider it is normal to have a sanded grout because it makes the grout more resistant to cracking. Grout joints less than 1/8″ should have a non-sanded grout or otherwise the grout may not fit into the grout joint. Some manufacturers make grouts that will work in both less than and more than 1/8″ wide grout joints. Grout joints that are 1/8″ wide can use either a non-sanded grout or a sanded grout. I always recommend the sanded grout because it is more resistant to cracking.
Putting a sealant (caulking) over a cementitious grout joint is not normal and I would not expect it to perform well.
I would not expect the Mapei grout to be inferior. Chances are the one you picked is different from what you expected it to me.
We recently installed a medium size marble mosaic floor, for some reason the tiler said we did not need to seal the tiles before laying. …. Mapei manhattan grey Grout was laid that is actually too dark for the tiles and as a result of not sealing has therefor stained the white marble grey! and also as its mosaic the grout needs to be higher as it is sharp on feet at corners.
So we have two dilemma’s, we need to try and remove the grey grout marks/haze from the tiles and prepare/remove some depth of the grout lines so we can apply more grout which I’m hoping we can pick a lighter white shade – to tackle the sharp edges.
Can you recommend a cleaning product to get the marble back to its original state? & should we removed the stains prepare the grout lines and then remove further stains? Or would it be ok to remove some of the grout lines now at the risk of further staining/ haze, then clean/remove stains after?? Hope that makes sense!!
First you need to determine is there a grout haze on the surface of the marble or is the marble stained as if something penetrated it. Its more likely it is a haze since if it is a true marble it can’t have more than 0.2% absorption which is technically impervious.
You have to be careful about what to use to remove the grout haze. It may be a cementitious haze or it may be a latex haze. Marble being a calcium carbonate material can easily etch from chemicals.
I would hire a professional stone restoration company who has a lot of experience. They could remove the grout then refinish the marble surface and grout with the new grout. They then could seal it for you.