One of the most asked questions by do-it-yourselfer’s is whether they should use caulk or grout in the corners. Industry standards state that a flexible material be used at all changes of plane. But! – if you ask a hundred different professionals you will more than likely receive fifty of each answer. While there are pros and cons of each, I am in the camp that uses caulk. That being the case, I will discuss using grout first. I’m backwards like that.
Using Grout at Changes of Plane
While the phrase “changes of plane” may sound a bit uppity or technical – it’s not. It simply describes the corner or edge of any surface that changes direction such as a corner, a wall to a floor, or a wall to the tub edge. Many professionals simply grout that corner as they do any other space between the tiles. There are a couple of things that must be taken into consideration before choosing this method.
- Your walls and the framing of your shower must be absolutely rock solid. I do mean absolutely. Grout is a cement-based product and as such is not meant to flex. If your wall moves your grout will eventually crack – it’s that simple.
- The space between the tiles at the change of plane must be large enough (for sanded grout) or small enough (for non-sanded grout) to be able to support the grout. That simply means that if you are using sanded grout you cannot butt the tiles against each other at the corner and expect to be able to force grout into it. It will not stay if the grout has no grout line to hold onto – if it is simply attempting to grab onto the face of the tiles at a 90 degree angle. There must be a grout line at the changes of plane.
- You must decide you are going to use grout at the changes of plane before you install the tile. You can then make sure to leave a line for the grout as well as adding additional support for any spots that may move even the tiniest bit (which it should not do anyway).
If you have taken the above points into consideration and still decide to use grout in the corners – go ahead. The big advantages of using grout here is that it will match all the grout lines and it will never have to be replaced. So although extra care must be taken to properly use grout at your plane changes, the advantages for some people are worth the extra time.
Using Caulk at Changes of Plane
There are several advantages to using caulk in corners and any other area where there may be a plane change or where tile meets another material such as your bathtub or sink.
- Unlike grout you are able to use caulk in a corner where tiles are butted against each other. It will stick to the face of the tile rather than needing a space between the tiles to grab.
- Caulk is flexible. If there is any movement the caulk is flexible enough to move with it and remain in place. It will not crack out or fall off.
- Caulk is waterproof – grout is not. Water will collect in corners such as where your tile meets the tub more than it will on the face of the tile.
- If your caulk does crack out or need to be replaced it is easily done.
The only two disadvantages to using caulk instead of grout are that you need to periodically remove and replace the caulk and, depending on your choice of grout, you may not be able to find a caulk that matches exactly. The first reason I consider to simply be regular maintenance and the latter is less of a problem since most major grout manufacturers sell matching caulk.
When to Use Grout
The only time I will use grout for a plane change is when I am using epoxy grout. Epoxy grout is bulletproof! OK, maybe it’s not bulletproof but you can hit it with a hammer a couple of times before it chips. (Don’t do that.) If you are using epoxy go ahead and grout the corners and changes of plane as well. Although it is not flexible it will grab the tile well enough to prevent it from splitting or cracking out. Precautions must still be taken but the Epoxy is strong enough to withstand normal structural movement.
How to Decide
Given the above parameters I believe caulk to always be the best choice. What you must understand about tile installation is no matter where you are installing the tile, it is always a structure that moves, no matter how minutely. Concrete moves, (the ground beneath it) that’s why it has expansion joints – to control where the movement goes. Most shower installations are over a wood structure of some sort. Whether you have drywall, backerboard, or a membrane, if you go far enough behind the tile, you’ll find wood. Wood moves, it’s just a fact of life. Humidity, weather, even the structure’s foundation all affect how much it moves. By taking proper precautions you can minimize the movement, but it’s still gonna move. Taking structural movement into consideration caulk is, for me, the logical choice.
Hi Roger
Can’t get away from me. For further reference.If you use tec accucolor acrylic silicone caulking can you go over once it is dry if you feel you may need a bit more to fill void?
Thanks,
Dick
Hey Dick,
Yes, you can. No problems with that at all.
Thanks very much for all great advice.
Dick
I plan on using spectralock epoxy for my grout in my grecian marble tub/shower surround. I read some people complaining about this grout cracking or causing the tile to crack in corners. Do you have any further or deeper thoughts upon this?
And if you end up thinking I can or should still use epoxy. Is it ok to grout it where the marble meets the tub?
Thanks so much!
Morti
Hey Mortimer,
The reason it does that is that two walls at differing angles will expand and contract in different directions – any change of plane will. Some tiles, and most marble, will crack before the grout does because the epoxy is stronger than the tile. When there is movement the stress has to go somewhere and it will go to the weakest part of the installation. You can use epoxy, you just need to use silicone at any change of plane rather than grout – where it meets the tub included. It is easier to silicone first, let that cure, then grout.
Yes, I am still rereading your pearls of wisdom. Yes, the pearls are making more sense every time I reread them, but sometimes still unclear. In your “Caulk or Grout in Corners” article you said the following, but then up above you seem to say the opposite. What am I missing here?:
When to Use Grout
The only time I will use grout for a plane change is when I am using epoxy grout. Epoxy grout is bulletproof! OK, maybe it’s not bulletproof but you can hit it with a hammer a couple of times before it chips. (Don’t do that.) If you are using epoxy go ahead and grout the corners and changes of plane as well. Although it is not flexible it will grab the tile well enough to prevent it from splitting or cracking out. Precautions must still be taken but the Epoxy is strong enough to withstand normal structural movement.
Thank you,
Ceci
Ceci,
I think he took my marble into consideration.
Morti
Oops.
Thanks,
Ceci
Every tile and stone reacts differently – marble is one of the most brittle stones. You need to use a flexible sealant there. I rarely use grout in corners, I simply put it in there as an example of when it CAN be used.
OK, just making sure I understand correctly. If one is using epoxy grout, is it good to use it in the change of plains if one is using mainly ceremic tiles and that glass border that I told you about before or should one use silicone? If good to use, what are the pluses and what are the negatives? Another thing I am a bit confused about. You know that gap between the hardiebacker and the membrane, does one stop the redgard right at the edge of the hardiebacker and not go at all onto the membrane with the redgard?
Please tell Sparky that I emailed Laticrete and they are going to be nice enough to give me a free mini kit of epoxy grout for my tile guy to practice with. Isn’t that the nicest thing? The local Laticrete rep. sure likes to talk. I think he loves this stuff. Yes, picked his brain too since he was once an installer.
Thanks,
Ceci
There is no good way to use grout in changes of plane – and it goes against standards. I simply stated that it CAN be done – that’s all. The correct material for any changes of plane is flexible sealant – silicone. And I have no idea what gap between the hardi and the membrane you’re talking about. If it’s the floor membrane then there should not be a gap between the two.
Most laticrete reps used to be installers, and most are adamant about the product and very, very helpful. It’s a huge part of the reason I prefer Laticrete products.
Oh, I get it now. Yes, am slow. Will use silicone since I am not a daredevil. Gosh, the Laticrete silicone is expensive. Yes, now have caulk to return since originally bought Laticrete’s arcrylic caulk instead.
Sorry I didn’t go into enough details. Yes, not typical of me, but am still sick as a dog. I’m talking about the shower area. I thought after one puts in the pan membrane(that PCP, oops, meant PVC liner), one puts in the bottom part of the hardiebacker(the wall) and I remember you saying/typing/whatever, that there should be a gap between the bottom of the hardiebacker and the membrane so wicking doesn’t happen. Did I get that wrong? If not, I am asking when one redgards the hardiebacker, should one go right to the edge of the hardiebacker(end of it) or should one go over onto the pan membrane? Hope that was clearer. No, that was not a trick question.
Yes, I can see why you prefer Laticrete. Nice guy. Could here the passion for all things tile in his voice.
Thanks,
Ceci
Just to the end of the hardibacker. The waterproofing extends up from the floor and water doesn’t levitate.
Roger,
Do you recommend grouting, caulking or nothing for the toilet?
Thanks again,
Morti
Forgot to ask if you think I should seal the marble before I grout. If I do sea,l do I need to cover the tile edges with tape to stop the sealer from interacting with the grout.
Thanks,
Morti
No need to seal marble before grouting unless it’s tumbled marble. If it’s shiny, grout first, then seal.
Either caulk or nothing – depends on how the base of the toilet looks against the tile. Grout will crack. If you caulk it leave an open area of caulk about three inches long in the back of the toilet – if it leaks you’ll notice it. If you seal it completely and it leaks you aren’t going to notice it until you end up in the basement.
Hi there, I have just finished bathroom, grouting completed should I use a seal on the coner
areas in the shower.
Thanks Rob.
Hey Rob,
If by ‘seal’ you mean caulk or silicone then yes, you use it in the corners as well.
Thanks for reply, I have noticed today some of the grouting come away, I will regrout area,
then silicone corner areas.
Thanks Rob.
Hi. I just ran into an issue with my newly built home. The corners of my tiled shower seem to have cracked. I’m assuming it’s caulk. I believe in fact the builder mentioned it is sanded caulk. I do know the color is slightly different from the tile grout.
At any rate I need to replace it and I went to pick up some sanded caulk but in reading the instruction on the back, it clearly mentioned not to use in areas that are exposed to constant water. I would assume being a shower wall, it would be exposed to constant water.
With that information I’m hesitant as to what to do. In fact I’m wondering if the current caulk is cracked because of this exposure. What do I do?
Hey Matthew,
The current caulk likely cracked due to excess movement at the corners. Movement in corners is completely normal, but sanded caulk eventually dries out and looses it’s elasticity. The best option would be a colored 100% silicone, which will remain flexible rather than drying out and cracking.
Hi Roger,
Did as you suggested in one of the answers and caulked the corners and between floor and wall. used tec acrylic silicone and looks fine. Today I grouted and some of grout got on caulk in corner and I did use grout sponge to clear it off but if some is still on caulking tomorrow that I did not see is there anything to worry about. Grout and caulking are same color.
2. Any suggestions to take acrylic silicone off tile in corners. In places I got a bit carried away. I did use the blue tape but when I went back after taking it off I went a little overboard.
Thanks for your help.
Dick
Hey Dick,
‘Bout time you get done with that damn shower!
Nothing to worry about with the grout over the silicone, you’ll likely be able to simply brush it off. You can take a utility knife and cut and scrape away the areas where you applied a bit too much.
You got that right. My wife thanks you. Appreciate all your help. Best site by far on internet. Again you should take all questions and answers and place in a book and make some cash. I am with you on helping people but you should also get some compensation.
Keep this site going
Hi Roger,
Using tec accucolor siliconized acrylic caulking to match my grout on all planes in my new shower. TiSome tiles where wall and shgower floor meet are 3/8″ and same in some of corners. Will the caulking be okay without backer rod or thin tile strips to place in there.
Can you explain how to put thin strips of tile into these thin areas if I have to do it or will I be fine with straight siliconized acrylic caulking.
Thanks for all your great advice.
Dick
You can’t really place slivers of tile in there without proper backing, and that’s rarely available in those small areas. The best thing to do is get some backer rod for the largest areas and silicone over it. The silicone by itself will be fine, but you’ll end up using a LOT of it to get those areas filled.
Our contractor installed porcelain tile using Sonneborn TX1 textured caulking sealant on our bathroom floor. He said its more moisture-resistant, as well as flexible. After reading your comment regarding use of silicone in lieu of grout, I’m wondering what you think of TX1 polyurethane as a replacement?
Hey Crewell,
Never heard of it. That said, I honestly don’t know how well it will or won’t work. It is intended for sealing stucco installations so it is likely weatherproof, but I don’t know anything about it. I guess if he’ll warranty its use let him use whatever he wants. Urethane-based sealants are high-end, durable products and that particular sealant is likely no exception.
Roger
I need your advice. I had a leaking shower stall. My plumber ruled out that the trap and the shower body was leaking as we cut holes. I am getting water behind the tiles. I am also sure that the tiles are set on regular sheetrock. It has been at least 15 years since tile was grouted. That is how long I have lived in the house. Do you recommend cutting out old grout or can I just go over with new. Should I als cut out any old caulky and re do.
Hey Robert,
I guarantee you are getting water behind the tile – it’s also completely normal. Tile and grout are not waterproof so regrouting will not solve your problem. What is likely happening is over the course of years the build-up of moisture behind your tile reached the maximum capacity that the wall would contain before gravity took over. Once that happens it will not stop. You can try re-caulking and regrouting but if it does help it will likely only be a temporary fix. Unfortunately if your tile is directly on sheetrock it is not properly waterproofed. The only thing that will permanently fix that is to rebuild the shower properly. Sorry.
Thank you for the quick reply – I am only looking to buy a year or two before we do a full down to studs remodel. What are you thoughts on the one piece drop in shower stalls. Do they need to be backed by Cement Board.
Hey Robert,
I prefer tile.
The one-piece kits are fine short-term provided they are sealed well at the seams with silicone. There are different types. Some need backing to support them and some are installed directly to the studs. The latter is likely what would be better for your situation.
Looks like the Regrout and re caulk has worked – Grout Sealant is only to stop mildew or stains. Is there anything that will repel water entirely to leaking behind tile
Nope, sorry. A good sealer will slow the rate at which water gets back there, but it will still get back there.
I recently had my bathroom remodeled with the walls tiled floor to ceiling. Where the tile meets the ceiling it looks a little uneven and I was wondering if I should use caulk at that point where the tiled wall meets the ceiling to make it look more even. The ceiling is painted white.
Hey Rosalyn,
Caulk would likely be your best bet. I don’t think I’ve ever seen a straight or level ceiling – no one ever thinks about that.
Great article, thanks!
I’m still in the grout camp, but caulk is the code in my area. I’d rather touch-up grout than re-caulk.
Best,
Mark
Sanded grout was used on tub area and caulking was done prior to the placement of the grout on tiles. Will that be water proof enough? if so, how to maintain to prevent mold and mildrew? Concern about grout cracking and leaking into the wall. Is it ok to caulk on the new grout on the along the tub line ?
Hi May,
Grout is not waterproof. Tile is not waterproof either. Really. Read through this: http://floorelf.com/answers and it will answer some very basic questions. Your shower should be waterproof before any tile is installed. The new grout along the tub line will likely crack out eventually (it’s called a change of plane and that one moves the most). The grout should be removed and replaced with just caulk or silicone.
Just tiled a bathtub shower surround. It was my first time and I left a 3/8-1/2 inch gap on the far end corner.(away from the shower head) Should I grout it or use sanded caulk or both? Thanks
Hey Michael,
Why’d you do that?
The best option would be to cut 3/8″ – 1/2″ tile strips to put in there. If you don’t wanna do that your next best option would be to get some ‘backer-rod’ at HD or a hardware store, stuff that in there, then silicone over it. If you put grout in there it will only crack out eventually.
i am updating my mother’s mid 70s house & am on the hall bath. the grout has black stains as does the caulk (i don’t even want to know what they are or why they are there.
ewwww) so i stripped out the old caulk & am going to mini-saw my way through the yucky grout spots. my questions: 1) 
do i use grout or caulk at the very top of the tile in the shower? it’s got about 12 inches of plaster (or whatever the wall is made out of) from the top of the tile to the ceiling so i’m not sure which is better (easy would be great but i’d rather it be right since it’s mom’s house). 2) 
do i regrout where i’m going to caulk? along base of tub specifically but there’s also a corner behind the toilet that has grout w/ the seam caulked too even though it’s not in the shower (the tile wraps around the bathroom & the floor tiles are teeny tiny). i saw your response to Carolyn saying to caulk then grout which says to me that i won’t grout where I caulk but WTH do i know so thought i’d ask anyway.
thanks for the advice!
Lori
Hey Lori,
I know what it is, and you’re right – you don’t wanna know.
Use caulk at the top of the shower, base of the shower tile, and in all the corners. No grout in any of those areas.
Hey Roger,
I am at the point where i am ready to grout my shower and shower ceiling. i was wanting to use matching caulk and grout. caulking where the plane changes and grout on the walls and ceiling and floor. Which should i do first the caulking or the grout? also i am using for the floor small broken travertine pieces on a mesh backing what type of grout should i use since there are really no grout lines just the spaces between the small pieces which varies.
Hi Carolyn,
It’s always better to caulk first, let that cure, then grout. It can, however, be done in either order. I normally grout then caulk simply due to time constraints – I don’t have time to sit around and wait for the silicone to cure.
Silicon caulking was placed under the grout around the tub. do I still need to apply caulking on top of the grout around the tub? Also should I apply caulking on the fixtures? see some gaps, especially where the fixture overlaps the tile and grout line.(what is the small hole on the bottom of the fixtures? Concern about moisture getting behind the fixtures.
Thank you.
Hi May,
No need to place silicone over the grout. And yes, you can silicone around the fixtures – it’ll help keep water out of there.
Hi Elf,
I just retiled my shower with 13″ tiles – it looks pretty good. I have left enough space to grout the changes of plane (corners) and am about the grout my tiles. My question is, should I put on a weather-proofing seal of some sort when I’m done? If so, what kind do you recommend?
Thank you.
Water proofing seal – not weather proofing – my bad.
Hey Jeff,
You meant ‘caulk’ the change of planes rather than grout them – right?
No ‘weather-proofing’ or water proofing seal required. You can use a tile and grout sealer if you wish, but it is only to prevent the tile and grout from staining – it doesn’t do anything as far as waterproofing goes. Your properly built substrate takes care of that.
My husband wants to use Caulk instead of grout on our kitchen backs- splash which has small 1inch ceramic and stainless tiles, he thinks it would be easier. Will that work?
Hi linda,
No, it won’t. It will work, but it won’t last. Silicone it not made to be a permanent material, it is intended to be replaced periodically. Namely once the seal is compromised (and it will be eventually) it needs to be replaced. Once that happens in those tiny grout lines it becomes a breeding ground for mold and bacteria. And it definitely won’t be easier.
Hi, read a lot of great tips and instructions on your site. i have totally gutted my small bathroom to the studs and i am having someone make a shower pan for me. my questions is about the ceiling over the shower it is bare studs right now (i can see into the attic) do i put sheetrock on first then durarock or just durarock?
Hi Carolyn,
Just the durarock is all you want up there.
Dear Elf:
Well, I got such brilliant advice on my question about grout caulking 6 months ago that I figured I’d come back for more! I am doing a simple reno in a 1/2 bathroom, and took off a row of older wall tiles in order to take out and replace the counter. We had no choice but to take them out, but now we’re beginning to think that those tiles will look really good in the “new” bathroom. So… any professional tips on cleaning old tiles that have cement and stuff on the back?
Hey Nigel,
Get some double-sided carpet tape, or something similarly strong, and tape them face down onto a bench. Take a belt sander to the back of them to remove all the old stuff. Wear a dust mask! It’s the quickest, easiest way.
i recently tiled my bathroom. i really don’t like how the silicone looks on the edges or corners (even though i totally understand it’s purpose). can i use epoxy grout around the bathtub and at the corners instead of silicone and then apply the grout sealant for extra protection? thank you.
Hey Agata,
Really, really not recommended. But yes, you can use epoxy grout in those areas. No need for the grout sealant – epoxy is essentially bullet-proof. Keep in mind that if there is excess movement the epoxy may actually cause your tiles to crack before the epoxy will. Really.
Hi,
What can I use for a bonding agent to make sure the silicone adheres to the tile and grout that is in the gaps between the tiles?
Thank you,
Greg
Hey Greg,
No bonding agent necessary for silicone – it’ll stick just fine to nearly everything. Just make sure that your gaps are cleaned out. You can use denatured alcohol to clean them and remove any dust or debris.
Your Blog says that Industry standards state that a flexible material be used at all changes of plane. I know this makes since, but can you please tell me where I can find this in writing? Is there a written industry standard that I can reference, and where can I get a copy. Thank you.
S. Morse
Hi Stewart,
The 2011 TCNA handbook for tile installation contains all specified installation methods. In every method under the heading ‘Requirements’ it states: “Caulk or seal penetrations, corners, and abutments to dissimilar materials with flexible sealant.” The ‘corners’ aspect includes all changes of plane. You can get a copy of the handbook from the TCNA here: http://www.tileusa.com/publication_main.htm If you specify a lot of these jobs it would be a good idea to purchase the ANSI standards handbook as well. You can also purchase them both on a CD-ROM.
Roger:
Thanks for the reply! I’ve been researching this for a long time and could never get a definitive answer so thanks. I’ve never worked with grout before so hopefully removing it isn’t that hard. I’m not too handy so I can see myself screwing up the tile somehow…lol. Wish me luck.
On another note, why the heck would the builder put grout along the tub and shower bases to begin with? They have to realize those joints are going to move over time and the grout is going to crack. I’m not handy at all but common sense just tells me you would want to use something WATERPROOF and flexible in those joints – not something that’s basically concrete.
Travis
Builder’s are normally only concerned with whether or not that particular joint will crack BEFORE the check clears – it won’t. After that they could care less.
Common sense isn’t so common, especially in construction.
Oh – and most people, builder’s included, actually think regular cementitious grout IS waterproof. Apparently they don’t own a driveway.
My home was built in 2001 and they used grout where the shower walls (and our tub) meet the floor tiles. The grout along these joints all have hairline cracks – and some are more than just hair line cracks. When the kids get out of the tub, they are dripping wet so all the water goes straight down to these joints. And when we get out of the shower, water drips off and into those joints as well. I’m nervous having so much water dripping into these small cracks.
Can I just silicone over these cracks or do I have to remove all the grout and then just silicone – or do I regrout again? If I have to remove the grout, how do you do it?
Thanks,
Travis
Hey Travis,
You’ll need to remove the grout in those areas and replace it with silicone. A grout saw and a hook knife are what I use (they can both be found at a big box store). If you silicone over the grout the cracking grout will eventually compromise the silicone.
Roger
Please help. I’m so glad that I found your cite. Grout was used at the “changes of plane” in my shower (5 years old). The grout in these corners is still intact but in an effort to remove mildew from silicon, I also removed some grout. I want to replace the grout with caulk but in one corner of the shower, the grout is about 7mm between the wall tiles and the fibreclass pan. Should I still remove that big piece of grout and can I effectively fill that gap then with caulk? I’ll appreciate your advise.
Hey Rina,
You can fill that gap with silicone if you want. It would be better to use a ‘backer rod’ behind it first. This is just a round piece of closed-cell foam you can buy at a hardware store and pack it into the gap then silicone right over the front of it. Much better method and it uses less silicone.