Your grout is cracking for one reason and one reason only: your tile is moving. That’s it. Okay, that’s not it – Unless your grout is non-sanded and was installed in the last 28 days – your tile is moving. That’s it. Yes, 28 days has significance, it is the amount of time it took my teenage son to clean his room. It is also the amount of time it takes for grout to fully cure.
So let’s figure out why your grout is cracking:
Your grout is newly installed – incorrectly
If you do have grout that was installed within the last 28 days then your grout is not actually cracking – it is shrinking. Either your grout lines are too large for non-sanded grout (smaller than 1/8″) or it was incorrectly mixed. NO! You cannot simply mix up more and fill it in. Read this post about adding more grout to your grout lines.
If your grout is not fresh, well, you need to repair the reason your tile is moving. And stop using your pogo stick in the house. Diagnosing the reason your tile is moving is extremely varied. It could be anything from inadequate deflection in your flooring for the type of tile all the way up to and including the aforementioned pogo stick.
The most likely reasons your tile is moving:
Your tile does not have proper thinset coverage
The most common reason I run into is improper coverage. This simply means that there is not enough thinset beneath your tile to properly adhere it to your substrate and support it. If there are any unsupported areas beneath your tile along the edge or in the corner of the tile, walking on it will eventually work what little support it may have loose and the tile will move down and up every time you step on it. The tile moves, the grout does not. The grout loses the battle and starts to crack out. By ‘crack out’ I don’t mean like that ridiculous Intervention show on cable, I mean it will start to crack and come loose.
To fix this you need to remove and properly reinstall the tile. If it is only one tile it may be an isolated incident in your installation and you will be fine. If you have cracked grout all over your tile installation it was either improperly installed or . . .
Your subfloor is moving
If you have a wooden subfloor and your tile is directly installed to it – go pick out new tile. That is more than likely an improper installation. While tile can be installed directly to plywood it requires a VERY specific method. And I do mean very specific. More than likely it is simply installed improperly probably by someone that did not know any better. If it was properly installed over plywood, well, your grout wouldn’t be cracking. Start reading this paragraph all over. Or . . .
Your backerboard was improperly installed
If you have Hardiebacker, Durock, or any other type of cementious backerboard beneath your tile it should have been installed in the proper manner. It needs to have thinset beneath it, it needs to be screwed down (properly), it needs proper spacing, etc., etc. Read How to Install Backerboards for Floor Tile to see all the things that should have been done.
More than likely there is no thinset beneath your backerboard. Thinset is not used to adhere the backerboards in any way – it is used simply to fill voids beneath the backerboard. It is placed there specifically to prevent your tile from moving. Moving tile leads to cracking grout. But you knew that – or you should start reading this page all over. This would be another time to start shopping for new tile.
Other reasons your tile is moving
You do not have expansion space around the perimeter of your tiled room. No, the tile will not expand – but your walls do. If there is no space between your tile and walls it will force all the pressure into your tile. This will cause cracking grout and, eventually, ‘tenting’ of your tile.
You do not have expansion joints in your tile. For every application there are specific spans of tile which can be installed before a ‘soft joint’ is required. This is simply a grout joint filled with a matching caulk or silicone to allow for movement without cracking your grout or tenting your tile. Most of these measurements are over 25 feet. So in English: if your room is not 25 feet long or wide this is not the reason your grout is cracking.
If your tile is on concrete – directly on concrete – your slab may not have proper expansion joints or the tile installation did not honor those. If installing tile directly to concrete (and you should not) there needs to be a soft joint directly above, or two inches on either side, of the slabs expansion joints. If not your slab will move differently than your tile.
And there could be a host of other, less apparent or less common problems. However, if your grout is cracking it is probably for one of the reasons above. The method of repairing it depends entirely on why it is cracking. Most of it, as with most tile installation problems, is due to improper installation.
Or your pogo stick.
If you have any questions about the proper way to repair your tile or grout just leave a comment. I answer every one of them – really, look around the site. I’m just super cool like that.
We moved into our house which was built on site in November 2012. After a few months, we noticed grout around the sink in the bathroom came loose. With our builder’s warranty we had them replace it and the tile(s) surrounding it.
Since then more grout has come loose around the toilets, bathtubs, and kitchen sink, including what was replaced. I’ve noticed it only comes up after any water sits on the floor for longer than 2 minutes. Our toilet leaked, and it took several minutes (10-15) to get the water to stop and cleaned up. Is there something (after we replace the grout) that we can put down that will keep it from coming loose when the littlest bit of water gets on it??
Hi Jodi,
The problem is not with your grout – that’s the effect. The cause is movement in your tile substrate. It would be my guess that it was installed directly to plywood, or you don’t have a proper substrate beneath the tile. When water gets into it the wood swells and moves the tile. When tile moves grout cracks and comes out. All the areas you describe would cause this with water exposure.
Hi Roger,
We moved into our new build home in July 2013, which I believe had been sitting, build complete but vacant for a few months.
On our moving in day we noticed that the grouting between our floor tiles in our top floor bathroom was crumbling and the tiles moving a little so the developer arranged for the tiler to re-grout but said that it will have been due to the house ‘drying out’ which may some time to calm down.
The grouting started to loosen within about a month from there and the developer wants to leave it until we’ve been here for a year to re-do but, 5months on, the tiles are moving around and the grout is crumbling and getting messy.
The developer is coming to see it this week and I’m sure is going to fob me off with the ‘drying out’ line again. Do you agree that this is likely to be the cause or could there be another issue?
Thanks in advance,
Semley
London, UK
Hi Semley,
That is absolutely not the cause. You have either an improper bond of the tile to the substrate, and improper substrate beneath your tile (like regular plywood), or an inadequate structural system for tile. It could be a combination of all three, none of which have anything at all to do with the house ‘drying out’, whatever the hell that means.
hi, im going to get my first kitchen ever.money is a issue as well so i dont want anything to go round.your help will be very very appreciated.we are goin to replace the kicthen floor this momday.now at the moment its very old concrete with holes and irregularities.so my husband thinks he should level it with wickes leveling compound.then put electric floor heating mats and then tiles on top .but im really worried about my tiles cracking and grout breaking …as this has happened in my sisters bathroom recently and she is heartbroken. …..could u please let me know if this is the right way to go pleaseeee AS SOON AS POSSIBLE PLZ3
Hi Faeza,
Yes, it can be leveled with leveling compound. The most crucial element is the bond of the tile to the concrete with the heating elements. You need to ensure that there is complete bond encapsulating the heating elements with complete coverage and support on your tile.
Hello Roger, We have a tiled entry/hallway, 8’x20′, 12″ square tiles, installed 17 years ago. About 1 year ago a portion of the grout line between two tiles cracked and broke, sucked up into the vacuum cleaner. Only about 6 inches in a straight line broke and are now gone – the corners are fine. I still have a bag of the orginal (sanded) grout, and after vacuuming out the now empty crack I mixed it according to directions and installed it. It blended fine and looked great, until a week or two later the new patch cracked and broke out again. I’ve repeated this now two times, and still it has broken out. Does this grout powder have a shelf life, or can you suggest something else to make the repair last? I don’t think movement is involved because nothing else on the entire floor has an issue. Thanks for any help!
John, Anchorage, AK
Hi John,
It would be my guess that there is a seam directly beneath, or very close to, where the grout is cracking. While grout does have a shelf life it simply won’t harden or will remain powder, it won’t solidify then crack. It is movement causing the cracking.
Hello Roger,
I installed some tiles today and didn’t use thin set, I accidentally used self leveling underlayment and grout instead. I botched the job but what are the chances of the tiles moving/becoming lose? How long will this hold up? What should I do other than redoing everything from scratch. Thank you.
Hi Lee,
I seriously doubt that will last any significant amount of time at all. I wouldn’t recommend anything other than removing it and replacing it properly.
I have a kitchen floor that 10′ x 28’length with 12 x 12 tiles and quarter-inch grout lines it has been down for two years but about two months after I was finished the grout lines started cracking shrinking I follow the instructions on the bag of the grout and mixed with water My subfloor is half-inch CDxthat was glued and screwed down I was wondering if I should’ve used a different additive to the grout other than water any suggestions would be helpful thank you
Hi Robert,
Grout admix won’t do anything at all. The problem is that you only have 1/2″ plywood beneath your floor. Tile installations require a minimum double layer of plywood with a total thickness of 1 1/8″. There is too much movement in the substrate beneath the tile, that’s why your grout is cracking.
Dear Roger,
I have a small, 1950’s Cape Cod beach house. When I bought the house 10 years ago, the second floor, which is just under the roof, had two bedrooms and a funky bathroom that we never used. Last spring I had the bathroom re-done by Lowes. I had a tile shower and tile floor put in, but I kept the painted/sheetrock walls, so I did not have the bathroom gutted to the studs. The contractor pulled out the old one piece fiberglass shower and the old linoleum floor, and I know that the contractor set the new tile inside the shower and on the floor on top of Hardiebacker. About 4 months after finishing the job, the grout in the corner where the shower tiles butt up against each other cracked from floor to ceiling. He came back and re-grouted the corner seams. Then a month later about 40% of the tile floor grout cracked. He came back and re-grouted. We noticed that a ceiling crack in the bedroom below the bathroom, which he had patched for me when he finished my bathroom, had opened up again and was now a bit bigger than it was before he patched it for me. The contractor from Lowes thinks the house is shifting because it’s built on an island and thinks i will need to re-grout regularly. What do you think? I would truly appreciate your input. This bathroom renovation has turned into a nightmare!
Sally
Hi Sally,
Any change of plane (corners) need to have silicone in them rather than grout. The two walls will move in different directions and silicone can compensate for that movement, grout will just crack. This will happen whether your house is shifting or not. Unless the crack in the ceiling is caused by water damage from your shower I really have no idea why it may be doing that, nor how to fix it. Sorry.
Hi, Roger,
What is your recommendation for dog urine proof or resistant grout? Or maybe a special type of sealer will do? We are finishing up this very nice dog play/boarding room using porcelain 6×26 wood tile. For what I understand, epoxy grout is not so resistant to dog urine.
thanks, Jessie
Hi Jessie,
Nothing is, epoxy comes closer than most anything else. Uric acid is still an acid. Given enough time it will eat away any type of grout.
My contractor has admitted to a drainage problem in my back yard. Pooling water right on the foundation and has agreed to fix it by extending the patio 6 feet. But he then followed by saying and I quote “This is our fault and we will fix it for you but, I’m asking you to keep it between us because if you tell your neighbors then everybody is going to want free concrete”. They have fixed two door locks , the front and the back doors. But my greatest concern is that I have noticed several cracks and holes in our grout. Also there are hairline cracks in all of our tile. This is all happening through out the house including huge cracks in my attached garage floor. We have only been here for a year. Im really irritated with the whole situation. I am an army veteran purchasing the first home in my families history and I am just heartbroken to know that all my hard work is just cracking away day by day.
Hi Tony,
I’m almost positive they don’t have a sufficient substrate beneath your tile, that’s why the grout is cracking. It may actually be installed directly over the wood. It wouldn’t surprise me.
Roger,
We have been in our home for 6 months. We have 12×24 tile, it is installed offset I believe 30, 70. It is installed over a sub floor. The grout is cracking everywhere. Virtually every grout line has cracking. The cracks look like they are mostly along the edge of the tiles. How do we best diagnose what is wrong. We were concerned with deflection when we were building our house and we got a letter from the manufacturer (through our builder) that it met “minimum code” is this enough? Our tiler wants to “fill” our grout. We said no, as it will crack again. How do find out what the cause is? Should it have been installed over a membrane? If so what kind. We know this is a big job to fix and we want to do it right. Ultimately is this builders responsibility to fix or our tilers (which they chose)?.We are still under New Home Builders Warranty.
Our hardwood also has gaps, and did not “tighten up” with humidity as they said. Are the 2 problems related or both just separate poor installation.
Needing your helpTanya
Hi Tanya,
It sounds to me like just poor installation. I have no idea whether the builder will cover it or not, nor whether or not it’s their responsibility. Call your local building department and they can give you more information. The problem is that it is installed directly on your subfloor. It needs a membrane or backerboard beneath it. Tile over regular osb or even a single layer plywood is not an approved method, your floor illustrates why.
Hi Roger. I’m trying to find a setting material for an unsuitable substrate. Slate tiles are delaminating in foyer of DIY owner-built house. I’m stuck w/ existing conditions, including finished floor elevation. Tiles (1/4″ thick, size varies 6×6 to 12×12) “glued” directly to 3/4″ plywood subfloor, with only a 1/32″ joint (bed). Beginning this thread, you said: “While tile can be installed directly to plywood it requires a VERY specific method. And I do mean very specific.” I sure could use a reference to that method, and any suggestions for both adhesive and grout products that might bond and flex under the circumstances. I’ve run out of ideas so I hope you can help. Thanks for sharing your expertise. Ed
Hi Ed,
I don’t recommend it. At all. You should not do it. At all.
That said, Bill has laid out the requirements on his FAQ page here: http://creativeceramicandmarble.com/Frequently%20Asked%20Questions.htm It’s #3 under underlayments.
Thanks for the reference, Roger. I appreciate your admonition and am well aware that not a single adhesive/grout manufacturer or installation pro would recommend anything other than spec (TCA, etc). This is a repair job, existing conditions; I cannot do nothing. But I can experiment. I’ll see if Bill can add anything to his FAQ post. Ed
Hi,
We have a large tiled area (all up 10m2- or approx 30 square feet). No expansion joints were put in. I am going to dig the grout around the skirting out and replace with silicone as this has cracked in some places, but is it worth digging grout out and doing expansion joints through the floor at the same time? Some of the tiles have started to raise,and others seem to have sunk (less than 1/4 inch), would adding expansion joints help this?
Thanks!
Hi Dianne,
10m2 normally does not require expansion joints in the field of tile, only around the perimeter. If your tile is indeed raising or shrinking that is a problem with your substrate, not the tile or joints.
Roger,
Jan again – thank you for your reply on the cracked grout issue.
We have delved further into the matter with one of our sub contractors about joist spacing/engineered drawings/TTMAC standards. The sub contractor explains that the floor system engineer isn’t doing their due diligence if they don’t abide by the TTMAC standards. I’m unsure if this is a floppy arguement or if there is truth? I understand that TTMAC standards say the joist spacing should be 16″ OC but the drawings we’ve recieved (from houses completed 2 years ago) is 19.2″OC. As a builder, we’ve never been told by the flooring contractor about TTMAC standards and hadn’t heard of them until they tried to use this as their arguement several years later. Wouldn’t one assume they had not done their due diligence to tell us that they won’t warranty their product if we don’t build our houses a certain way? I think this is more of a rant than a question, but I believe I’ve got two questions in here.
TTMAC standards are a key element. The standard has to do with the deflection ratio of your floor – how bouncy it is. Every joist system has a number related to that equation. It is called the…wait for it… deflection ratio (engineers aren’t known for originality
). The minimum deflection ratio to successfully support a tile installation is l/360. The higher the number the stiffer your floor, the more able it is to successfully support your tile.
If, when the house was built, that particular floor did not have tile installed on it then 19.2″ oc joists may have been perfectly acceptable to meet the minimum live and dead load requirements for something like vinyl or carpet. With regular wooden joists (2 x 8, 2 x 10, etc.) then 16″ oc is the norm. However, with engineered joists (the two smaller pieces of solid wood with thinner plywood between them) then 19.2″, or even 24″, may be acceptable to meet minimum deflection and load requirements. IT DEPENDS ON THE ENGINEERED JOIST MANUFACTURERS SPECIFICATIONS. The floor must meet building requirements to pass inspection (even in Canada
).
Bottom line: If your house was built with tile in that room then the engineered joists meet the l/360 requirement even at 19.2″ oc. It was required to pass code. The joist manufacturer can tell you the deflection number at that spacing. If it does not then your builder is responsible. If that room did not have tile then it was up to the tile contractor to ensure that the floor met deflection requirements, and take steps to get it there if it did not, before tile was installed.
Unless they have specs from the joist manufacturer (I’m assuming that they are engineered joists) then he has no idea whether the l/360 requirement is met or not. If they are not engineered joists you can check the deflection ratio here by inputting your particular specs.
hello, I am the second owner of a flat. the floor grout keeps on washing away with use. I have replaced the grout several times but it does not last long. am I using a grout not suitable for floors, or what do you think is happening.
thanks for time
Hi Paul,
Either your substrate is not built properly to support your tile installation or the bonding of your tile to the substrate is inadequate. Cracking grout is indicative of movement of the substrate to which the tile is bonded or an improper bond to it.
Hi Roger,
We have lived in the house we built for 11 years now. Our kids bathroom has had grout cracking out in pieces for several of those years. I want to mention the 12×12 tiles were installed on the subfloor and the bathroom has floor heating which is heated by forced hot water pipes installed and deflected under the subfloor. We have one minor hairline crack in a tile near the toilet, but no tile cracks anywhere else in the bathroom. The first place we noticed the grout cracking and lifting away (every so often new “pieces” will come up when I vacuum) was near the tub which is a fiberglass one piece unit. We are now ready to remove all the grout and redo. My questions to you are: Is there any particular type of grout we should use? The floor heat is now on for the winter (and with the door closed the bathroom can get as warm as 78 degrees) – is this a bad time to grout? Are there any spots we shouldn’t grout? Is there a really good tile and grout sealant out there that you would recommend? Anything else we should know? Thanks for your time, Jen
Hi Jen,
Your grout is cracking due to movement of some sort, as mentioned above. There is no combination of grout and sealer that will prevent it. Until you fix the underlying problem your grout will continue to crack. When you say the ’tiles were installed on the subfloor’, do you mean on the wood? Or is it concrete? If wood that is your problem, it needs a proper substrate on which to bond. If concrete it is indicative of improper thinset coverage and/or bond.
Grout is concrete, essentially. It will last as long as your tile lasts. If it is cracking it means something under your tile is done incorrectly, not that something is wrong with the grout.
I had a water break in my house and got 2-3 inches of water throughout the house. The contractor put new baseboards throughout the house. I have already had them come out one just a little over a month sine they completed the work because of cracking of the grout between the tile and baseboards. some places the grout just broke out. They came back out and regrouted over the existing grout. I have cracks and broke pieces again. What are they doing wrong? I want it done correct. Please help me.
Hi Terry,
There should be no grout between base and tile. It is a change of plane, it needs to have silicone, not grout.
Roger,
I have a three year old house, it’s built on a concrete slab, I have tile in my bathrooms, kitchen and laundry area. The grout has only cracked in half of the kitchen area, it was re-grouted once two years ago and started to crack a couple months afterwards and continues to spread but does not go past the kitchen into the adjoining dining area. Can you offer any ideas on what the problem is? Thanks for your time.
HI Dan,
The kitchen is likely on a separate slab or you have an expansion joint across the kitchen which was not compensated for with a soft joint above it. To fix it you need to locate the expansion joint in the slab and place a soft joint directly above it. As the two pieces of the slab move it will crack that grout line, placing silicone in it can compensate for it.
Hi,
I recently installed tile bathtub/shower walls and a tile floor. I noticed some hairline cracks in both the floor grout (sanded) and the wall grout (unsanded). I tried to install everything by the books so this cracking is frustrating. My question is – should I have filled the tub with water prior to doing my tile work? The tub was empty when I did the floor and walls and I’m wondering if the cyclic filling and draining of the tub could be impacting my tiles? No tiles are cracked, but the wall tile grout is cracked from the top of the tub to a height about 1.5 – 2 feet above the tub.
Thanks in advance for any suggestions!
Hi Jay,
It could be the problem only if the tile is butted directly against the tub – which it shouldn’t be. There should be a 1/8″ gap between the tile and tub and it should be filled with silicone.
The tile is not touching the tub at all, but the backer board is resting directly on the tub flange. Could that be the issue since the tile is adhered to the backer board?
Yes, there should be a gap there as well. The two different materials will expand and contract at different rates. Is there any way you can get a blade of any sort in there to cut expansion space? If not, you can remove the bottom row of tile and cut one in there.
Roger,
Thanks for the input. I’ll have to remove the bottom row of tile to be able to cut a gap between the backerboard and the tub flange. A pain in the ass, but not the end of the world.
We bought a house in June (and 6 days later got a job promotion out of state but that’s another story…) and notice a few cracks in the grout of the tile in the kitchen and entryway. The cracks are getting worse and more, so I did a bit of internet research (and some poking around in extra supplies the previous owner left) and found non-sanded grout. The grout lines are probably 1/4 inch. My question is, can we just replace the grout? If not, can we save the tiles and re-use them with the right grout? Some of the tiles are uneven (height-wise) and a few have small cracks in them and would need to be replaced. Now, if we were staying in this house forever (as was the plan when we bought it) we would replace the whole floor eventually. But since we are just trying to fix any problems so we can sell it in the spring, we don’t want to drop a ton of money on this. Any help you can give us would be greatly appreciated.
Hi Erin,
Yes, you can scrape out the unsanded grout and replace it with sanded grout.
Roger,
I’m glad that I found your website. I’m about to undertake my first tile project on the bathroom floor and I’m not sure if I’m prepared. Here is the background. The bathroom floor is about 6′ x 9′ but it is definitely not a perfect rectangle. I have a lot of obstacles like the tub, vanity, interior walls, etc. that make the project such that there are A LOT of corners and edges.
The house was built in 1946 and is a split-level with tongue and groove wood floors over wood joists. There is currently Vinyl Composition Flooring over the wood floors in the bathroom which I will just tile over. My biggest concern is that there is creaking in the floorboards when I walk in the hallway (not particularly in the bathroom) and I want to make sure that any deflection in my wood flooring does not crack the grout or tile. For this reason, I went with an underlayment, crack-prevention thin set, and an epoxy grout. I opted for this particular underlayment as opposed to a backerboard for ease of installation and to keep the elevation of the flooring down.
I am using 2″x2″ Octagon ceramic tile, FlexBond Thinset “Crack-Prevention” Mortar, CEG-Lite Commercial Epoxy Grout, and EasyMat Tile and Stone Underlayment.
What do you think about this? Is there anything I should pay close attention to? I’m a neurotic to be so concerned with cracking? I have one shot and want to make sure I do all the proper prep work and get the flooring down solid.
Hi Stephen,
It would be better to install an additional 1/2″ layer of plywood over that vct first, then the easymat and tile. If you do that you shouldn’t need to worry about any cracking at all.
We are retired and on a very small budget. Grout cracking, intalled over plywood with hardiboard screwed( countersunk) into sub floor.
Can we remove cracked grouting and then “grout” with a flexible grout caulk? We really do not have the money to completely remove and redo tile.
Hi Ellie,
Sorry for the delay, you were in the spam folder for some reason. I don’t know what ‘flexible grout caulk’ is. There is no such animal to my knowledge. If you mean regular sanded caulk then no, that won’t last. You can regrout it with regular grout, but you’ll need to remove the existing stuff and it likely won’t solve the problem over the long-term. There is some underlying issue, likely no thinset beneath the backer, and regrouting simply won’t fix it.
Hiya
We renovated a very old kitchen 6 months ago – we knocked down a wall to make the kitchen bigger and noticed that the two adjoining rooms had a different flooring as was on different levels!- one had wood and the other concrete! we, including the builders leveled the whole floor and sealed as required. However a few tiles in different areas of the kitchen move really badly and the grouting is popping out and is disintegrating beneath my feet…the floor was very well leveled by professionals and the tiles were laid well, so what do i do??…..HELP ME, I am at my wits end :-( Thanks soooooo much in advance.
Hi Jo,
I’m assuming that the cracking is located somewhere around where the two different substrates meet? Where the base goes from wood to concrete beneath the floor? If so then all you need to do is remove the grout in the joint directly above that transition and replace it with flexible sealant (silicone) rather than grout. The differential expansion between the two materials is causing stress in your tile installation and causing grout to crack.
Hi. We are remodeling our laundry room. About 6 months ago we installed slate tile over a thinset, cement board and morter. We used a sanded grout in grout lines that are a little smaller than .25″ wide. In the last month or two we have noticed fine cracks in our grout lines.
I feel that we did the proper research and installed everything correctly. The only thing that seems to make sense is over the course of this remodel we have had to move the washer and dryer in and out of the room (over the tile, of course) with in a day or two of the tile install being done. could the weight of the washer and dryer on an appliance dolly cause these cracks?
I’m not looking forward to replacing grout and going without a washer and dryer for 28 days waiting for it all to cure.
Help!
Hi Amy,
Sorry for the delay, been out of town at the new Schluter facility all week.
Yes, moving heavy appliances around a freshly set floor can cause a bit of movement. I would first try to regrout it by removing the existing grout then grouting with new. If that was your problem then that will solve it. If it continues to crack you either have tile which is not correctly bonded (and that may have derived from moving the washer and dryer in as well) or an inadequate structure beneath your tile to support that installation.
roger,
I recently had some cracked tiles repaired on my kitchen floor, between my sink and fridge. the repair man used a grinder to remove the old grout and then broke the tiles and removed all the old mourter from the floor in those spaces. he then said that the old tiles were not back buttered when they were first put down 8 years ago. the tiles are in place but the grout has cracked twice in a few places. there was backerboard used and these are the spots that the grout is breaking. the grout used is a sand based grout. I really don’t want to replace the floor. do you have any ideas?
Hi David,
Sorry for the delay, been out of town at the new Schluter facility all week.
If not backbuttered some, or all, of the tile may not bond well. Since those particular tiles had cracked grout that is likely what happened. It doesn’t necessarily mean that none of the floor bonded fine, just that those did not. It may be fine after those are repaired, just watch for further grout cracking in other areas.
Roger:
I had my tiny bathroom redone more than 5 years ago. There is a 2″ grout line that has given way, just in front of the tub. Usually, this is hidden under the mat and not seen very often. I noticed a small hairline crack a few months ago and ignored it. The other day I noticed that the 2″ area was now pulverized to dust and I can’t ignore it any longer. No other areas seem to be cracked or broken. What steps should I take to repair this issue? Is this just a remove/clean out/apply patch kind of a thing or something more? How do you determine if the thinset is not sufficient? Since it is only this one small spot, I am leaning toward the tile corner may have had some movement….. However, since it is in front of the tub, could improperly sealed grout crack out after repeatedly getting wet?
How would you approach this kind of small issue?
In advance, thank you so much for your time and experience. I really appreciate your efforts and help.
Cheers,
Rachelle
Louisville, KY
Hi Rachelle,
Grout getting wet won’t do anything to it, sealed or not. You did not mention what type of substrate your tile is installed over but if water seeped down into your substrate and subsequently began to swell the wood then that would cause cracked grout. Being as it’s only right in front of the tub that would be my guess. You can try to regrout it, but if it ends up cracking out again, which it likely will, then it’s a matter of removing the tile in that area and repairing / replacing the substrate.