This is a question I get asked from time to time. The short answer is no, you should not. Although grout does not add to the stability of the tile installation (unless it is epoxy grout), you still need to grout it.
Why you need grout
A lot of natural stones, namely granites and marbles, are manufactured to be consistently sized. For the most part all the tiles are identical. This makes a lot of people want to install them without grout lines. Although in some people’s opinion butting the tiles against one another looks better than having even the smallest grout lines, it is not a recommended installation procedure.
Even if all the tiles look like they are the same size I can nearly guarantee they are not. Unless they are “rectified” they will differ, even if only a tiny amount, from tile to tile. Attempting to butt the tiles will result in a “jog” of the lines between them. The larger the area, the more those lines will run off. By leaving even 1/32 of an inch grout line you will be able to compensate for the difference in tile widths.
You also need grout to ensure that nothing can get between your tiles. Look at it this way: would you rather have a very small grout line filled with grout or a very, very small grout line filled with spaghetti sauce? No matter how tightly you attempt to butt the tiles, there will still be the tiniest space between them. Not grouting them leaves open the possibility of all types of unruly things filling them. Then you have to clean them out risking the possibility of damaging one of the tiles.
The final reason I’ll throw out there is that no matter what substrate you are using there will always be movement. Always. Placing the tiles against each other will eventually damage them. If you continuously rub the edges of two tiles together one or both will eventually chip (and you need to get out of the house more, or at least find another hobby). The expansion and contraction of wood or concrete will do the same thing. Although you can minimize this using different underlayment materials, it will still move.
I hate grout, I really do. If it were up to me I would install most tile and all granite and marble with no grout lines at all. I can’t do it. Even though it will look better initially, eventually it will ruin the tile. The best thing to do is use the smallest grout line your particular tile will allow and get a grout that closely matches the tile. For most granite and marble tile I install I use either 1/32 or 1/16 inch grout lines. In most other tile I will use 1/16 or 1/8 inch lines. I try to use the smallest grout lines the tile will allow.
To figure out how small you can go, place nine tiles in a 3 X 3 foot square butted against each other. Measure corner to corner diagonally both ways and see how close they are. If they are within 1/16 inch that is the size grout line you can use safely.
Please resist the temptation to install your tile without grout. Grout sucks, believe me, I know. By choosing a matching grout, though, you’ll be happier in the end and your tile will last significantly longer.
Update: The photos below were sent in by a reader asking why his tiles were cracking. They are travertine tiles and the cracking is a direct result of having the tiles butted against each other with no grout lines. This is what can happen.
Hi Roger,
I am plcing 12 inch granite tile around a sheetrocked/painted fireplace with a row of tile on a concrete floor. Do you still recommend the grout? The tile on the floor will seldom be walked on and all told we will only use 5 tiles across and 5 high on the wall.
Thanks
Hey Jim,
It still needs grout. Around a fireplace it’s gonna move more than almost anywhere else in the house, you don’t want to butt it.
Would recommend installing the wood baseboard before grouting the tiles. Any gap between tiles and baseboard would be filled.
Thanks
MG
Hi MG,
Grout before the base. If you have gaps between the tile and base it needs silicone, not grout. Grout will crack out of there.
Hi–
I am doing a tile backsplash in a kitchen with white marble tiles–they’re tiny, raw and uneven/textured and I was told NOT to grout it—but everything you talk about talks about grouting–so, should I? And in terms of cleaning it if I do–you usually just wipe down with a damp sponge–can’t do that on this—it’s rough edges–what do you recommend? Thanks!
Hi Cass,
I’m assuming you have a stacked, split-faced marble? If so, my recommendation is to find a different tile for your kitchen. That particular tile does not get grouted. It is therefore unsuitable for use in a kitchen or wet area. Stones like those are made for stuff like fireplaces. If that isn’t what you have you’ll need to let me know exactly what tile you have before I can try to help.
yes, that is what I have–sadly it got installed it before I got back to your post–I found a marble sealant–might that help? I used Bondera and waterproof seaming tape…
It’ll help, but it definitely isn’t a desired product in a kitchen. I would seal it and make sure you clean it well regularly.
thanks for your help!! I appreciate it!
I guess I should have looked at this part of your web site before asking a question that had been asked.
DUH.
Oh, you made it.
Disregard my answer then…
I’m impressed by your writing. Are you a professional or just very knleawdgelboe?
Hi Marge,
Thanks! I am a professional. A professional tile contractor. With a degree in physics and a healthy disdain for people who butcher language.
Roger – thanks for the speedy reply – dropped some more cash on your tile tips – more power to you (though I managed to completely miss taking advantage of your special offer – more for the troops i hope). You answered my previous question beautifully, but I’m now freaking out about the tub flange. (man this tile work gets you into a bizarre state of mind ) I understand that my kerdi should be silicone sealed to the flange – thinset will NOT bond to the flange (you told me that). But should my wall substrate backerboard overlap the flange (stud-flange-backerboard (overhanging flange) – Kerdi ) or be behind it (stud-backerboard-flange – kerdi) – sorry to be a pain. I checked out various interwebs and a whole load of know-nothing types pontificate all ways – i’m back here where i can get solid advice.
Thanks
Hey Nick,
It should overlap the flange. Studs, tub, backer.
Since thinset is initially alkaline, I think, can acid help remove excess where we allowed “squeeze” to dry before finding your site. If so, would acetic acid (vinegar) be a good compromise between efficacy and safety to the underlying thinset we do not wish to disturb? Does Hydrochloric (Muriatic) acid have a role?
Thank You!
Your answers are clear, concise, logical and very reasonable.
There is an awful lot of hot-air, meaningless fluff on the web; Your site is head and shoulder above!
Hi Dennis,
Once cured any type of acid will be more harmful to the tile than it would to the thinset. Hydrochloric acid would not be a good idea. It is a very aggressive acid on tile surfaces. Your best be is to slowly scrape it out of there.
Came across this site today – awesome. I’ve even spent $18.95 – hey, I’m about to drop a ton of money on tile, backer board, etc etc – this is probably the least that I’ll spend for anything on my project and likely to have the highest return.
I am currently in the demolition phase of a bathroom re-tile/re-floor. As is normal I discover more awfulness with every step – big problem is the shower/tub and where it meets the floor – water slopping out of the tub has clearly run down the external tub side and rotted out the unprotected lino floor. So I’m ripping out floor and replacing it with a double layer of 5/8″ plywood, onto which I plan to put backerboard before tiling – but having read your awesome book I know that I need to waterproof the floor especially given its past history – how do I ensure that water running down the side of the tub (kids! What can you do?) and sitting on the floor doesn’t penetrate any gap between tile and tub and rot out my new floor – I assume some cunning use of Kerdi – help appreciated – Thanks
Hey Nick,
There are several ways you can do it, but most incorporate a waterproof membrane of some sort on the floor outside the tub and a bead of silicone between it and the tub. If you use kerdi there you can butt it right up to the tub and silicone that transition.
Hey Roger, I am using 8″ X 40″ Cerdomus porcelain tiles that have a wood grain. I’d like to get as close to a wood floor look as possible. What grout size would you recommend?
Hey Stephen,
The smallest viable grout line size with most of those tiles is 1/8″, that’s what I set mine with.
Hi Roger, this site is awesome! I am planning on putting marble tiles on a guest upstairs bathroom. Small space about 30 square feet. The original flooring is vinyl. How do you think I should proceed?
1. Moisture control on top of vinyl
2. Then wonderboard
3. Then screws
4. Then marble installed with thinset (1/16″ grout line)
5. Non-Sanded grout
6. Sealer
Am I missing anything?
Thanks!
Hi QB,
Yes, you’re missing stuff and you have stuff you don’t need. Ideally you should remove the vinyl and underlayment. The problem is that the underlayment is likely luan, which is very thin plywood and belongs nowhere near a tile installation. Should you choose not to do that the steps will still be the same:
1. Thinset over subfloor (or vinyl)
2. wonderboard
3. board-specific screws (not just drywall screws)
4. marble with thinset – whatever sized grout lines you want
5. non-sanded grout
6. sealer
Thanks Roger! Sorry for the late comment as been busy with the remodel. I chose not to remove the vinyl and just put the marble on top of it after putting in the moisture control layer. Worked just like you said :-) Thanks for all the advice and regards! Your site is great! :-)
Our plumber tiled our bathroom, but wasn’t ready to grout at the time. He removed the toilet and tiled without grouting, he wanted to be able to use the toilet while they were working. So he used thinset as grout under the toilet. Is this ok or should we have him remove the toilet when he is grouting and get the thinset out of the grout lines & grout under the toilet?
Thanks
Hey Steven,
It’s fine as long as it doesn’t bug you. It would drive my OCD absolutely batshit, but it won’t hurt anything.
I am putting travertine 12×12 tile in two bathrooms. The travertine is from Mexico and is called roho or terra cotta. It varies in color with coral, salmon and cream mix. It also has some black spicks. So I went with black grout. Is this a mistake? Should I go with a grout that is more the color of the tile like a straw, biscuit or chamois. Also chose a 1/8th in spaced. I have never put down a tile floor before and the travertine is so beautiful I am worried about making a mistake color wise on the grout. The travertine is honed and filled.
Thak you
Hi Alisa,
The correct grout color is whichever you like. If you like the black then it’s the right color. You do want to get a good sealer, like miracle sealant’s 511 and seal the travertine really well before you grout.
Hello Roger;
I am doing a large master bath project (Asian not Roman motif) and I am using DAL’s Kimono Silk tile for the floor (24″by 24″). The tile has a fabric look to it and alignment marks so the patterns stays consistent. I have been reading your posts and you are saying do not do a zero grout line. But you also said for some tile you might get around it with a grout bag etc. The 2 questions I have are:
When putting the large tiles down should use thinset or anAcrylic adhesive (e.g. Acrylpro Tile Adhesive)
2)Do you have a recommendation on how to possibly get the best look and feel for this tile. The reason I chose the large tiles was to reduce the Chopped look of a standard grid/grout lined tile (Tatami mat was what I was going for)
Thanks
Hi Lynndy,
1. Always – ALWAYS use powdered thinset for large format tile. The adhesive will NEVER cure under those.
2. Use a 1/8″ grout line and find a grout that matches the tile well. If it’s the tile I’m thinking of I believe mapei’s ‘straw’ (I think) matches it well.
Never use zero grout line. The grout bag recommendation is for a completely different type of tile, stacked stone, which has little or no grout line to it. That, however, is nowhere close to what you’re using.
Hi, I’ve just noticed that my tiler has laid the marble tiles in the shower too closely together – some have 1/32 space but some I can’t even get my fingernail in. He claims that he’s going to grout but I don’t see how grout is going to fit in some of those spaces. What do I do? Will the tiles need to come out or is there a tool, like a dentist’s type of drill, that can widen the gap between tiles? Should I get a new tiler to repair the work or instruct this one on how to repair? A friend recommended the tiler but perhaps he’s never worked w/ marble? Help, I’m stressed! Thank you.
Hey Kate,
There should be an absolute minimum of 1/32″ grout line – that’s pushing it. Your shower substrate will be moving, it’s completely normal. If the marble is butted it may chip the edges when it does that. I would wait and see how it turns out and take it from there.
Many thanks!
1) should I get him to do a small area of grout and see how it fills the crack and if it seems to be secure (I understand that substrate movement may make it fail over time even if it seems secure at first)?
2) Can a groove/channel be cut to widen the cracks between tiles so they can accept more grout?
3) Or do the tiles need to come off now and be reset?
Thanks, again!
I would let him do the entire thing first. See how it turns out. If you’re not happy with it at that point make him fix it – you’re paying for it, eh? A larger grout line CAN be cut out of it, but it tends to chip the hell out of the tile. If it needs to be fixed after he’s done replacement is the best option.
Hi Kate, I was wondering if you could share how the shower turned out after all?
my kitchen floor has one inch of gyp-crete over three quarter inch osb. can I tile directly onto the gyp-crete using flex bond thin set?
Hey Keith,
You should seal or prime the gypcrete first. When I say seal I mean a product like redgard, not a concrete sealer. One that is intended to be used with thinset. Tec has a good primer for concrete and other substrates, you can also use the primer intended for self-leveling cement – you can get that at home depot.
thanks Roger! You’re awesome!
Roger,
I’m laying granite tile in a small bathroom where I’ve removed the ugly old shower.
A curved glass corner shower will be installed in it’s place. Should I install the shower first then cut the tile to fit or can I run just enough tile under the edge of the shower base before I put it in? I’m just trying to get a nice clean edge with out cracking them. I’ll be running them under the toilet up to the flange as well so I thought that would work. Thanks, BEN
Hey Ben,
You can install the tile then the base over it. You’ll need to place tile around the back perimeter where you’re installing the shower as well so you have an even height supporting the base, but it’ll work fine doing it that way and will give you a more finished look.
Hi,
I bought glasstile to goaround my gas fireplace and want to but the 1″ suares together, leaving no room to grout. Can I do that?
Hey Darren,
You can, but it will crack. So you really shouldn’t.
i have just gotten some glass mosiac tiles for my backsplash they are wavy tiles and do not have any lines in between that would fit any grout. if i grout between the tiles instead of butting them against each other how do you recommend grouting them you cant use anything flat to spread the grout into the lines because the tiles are wavy. what do you suggest.
Hi Tammy,
If they are the ones that are wavy in and out (rather than side to side) in the y-axis then you don’t grout those.
no these are the side by side it is the “Verde Wave Mosaic Glass Tile” that i purchased. i have laid tile before im just not sure how to grout this kind of tile because i cant use a float because of the wavyness
Those are what I meant – wavy in the z-axis, not the y-axis. Geometry brain fart.
You don’t grout those. You can, but it needs to be done with a grout bag, non-sanded grout and a whole lot of time.
When you say epoxy grout what is the name brand to use for travertine tiles and can I mix it with a little sand grout to match the color,,,if not how do I get to match the color with the sanded grout that is already in place,,also does the epoxy grout need to be sealed if so what sealer would you recomend around bath tub on top of the tub,,,thanx
Hi Paul,
When you say ‘when you say epoxy grout’ I have absolutely no idea what you’re talking about or what answer you may be referring. I don’t know where I said that. If you’ve already asked me a question, and I’ve answered it, and you are referring to that answer I need you to ask this question as a response to that answer. That is exactly why I have that request right at the top of the box in which you’ve typed this question.
I have (literally) over 16,000 questions that I’ve answered on this site, I can’t remember every one of them.
Sorry.
I can tell you that you’ll be able to match nearly any color with a spectralock epoxy grout and no, you CAN NOT mix sanded grout with the epoxy. Epoxy grout does not need to be sealed. If that doesn’t give you what you need I need to know what your previous question and my previous answer was.
Roger, you wrote “epoxy grout” in the third sentence of this article (at the top of this page). “Although grout does not add to the stability …”
Oh.
Sorry about that.
Same answer, though.
when my brand new shower was about three years old, the grout surrounding the mosaic tiles on the floor began to show patchy areas of gray. i thought this was mold but no cleaning product would touch it. a grout replacement contractor came over and said the thinset was not properly removed before the tile was grouted and, with routine cleaning, the grout has worn away, thereby revealing the thinset below it. does this sound correct to you? the company that originally installed all my tile will not stand behind their work even though i began complaining about it before the shower was five years old. can this problem be easily remedied? thanks
Hi Danielle,
Sounds like he’s right to me. If the thinset is not cleaned out of the grout lines, especially in mosaics since there are so many more lines and they are usually not as thick a tile, then it can show through the grout either right away or after abrasion from cleaning wears down your grout. It can all be removed and regrouted. The high parts of the thinset will just be removed with the grout in the same manner.
Hello Roger,
I’m planning to please my missus with granite tiles in the kitchen. Black Galaxy seems to be the thing – I have the option to buy with or w/o chamfering ( hardly visible) on the edges. Do I need chamfering other than placed were the egde will be exposed which I assume we’ll to done in situ by using the proper tool for it..?
Thanks, Viggo
Hey Viggo,
You don’t need it, just be sure to inspect every single piece when you pick it up. The biggest reason for chamfering on natural stone is to prevent it from edge chipping during shipping. Really. You can always use a rubbing stone to knock down any edges on the ends where needed as you set the tile.
Thanks for quick feedback – Great
Roger,
I have been finishing a basement bathroom on a concrete slab and I plan to build a tile shower and a heated tile floor on the slab. Unfortunately, I started the project before I found your website (which is light years beyond anything else out there!). I was using a tile book from Lowe’s which called for concrete for the preslope and treated lumber for the curb. Granted, this lumber had been sitting in my garage for a few years but not recommended by you, for obvious reasons. I have already put down the PVC liner and use sticky mud on the curb. Should I break it all apart and start over? Or is my dog destined for a firey death?! Please help me save my dog and my project. Thanks.
Hi Aaron,
Unfortunately the pressure treated lumber will need to be removed. It will eventually begin off-gassing which will cause it to shrink. Although it’s been in your garage for years, it has been exposed to humidity and allowed to acclimate to the environment, which causes it to be stable. It is now sealed up away from the environment and has no way to stabilize to it’s current moisture content and size. It will begin to dry out and twist. Not good for your tile. Sorry, I know that’s not what you wanted to hear. Better now then the question in six months about why the tile on your curb is cracking, eh?
Hi Roger, sounds like you are dishing out some very good information here. Reading Lynn’s question reminds me of how many times I’ve had to dig out my own thinset (better done when wet) before grouting or digging out spacers encased in thinset between two heavy vertical tiles.
Looking at Steve’s question, I recall removing 5 cracked Marble tiles in a bathroom floor with no real grout lines but just enough to fill the very tiny chamferd edges. I cut the inside of the tile out about 1/4 inch inside the grout lines around the entire interior of the Marble tiles then very very carefully began to chisel out the tile from the center out. I still managed to damage an additional 4 adjacent tiles.
I give folks like Steve a lot of credit for tackling that chore.
Nice sites Roger.
Ed
Hello Roger,
What is the best way to break out and remove a center tile with out damaging the others. I was going to X cut it as close to the edge as possible then use a chisel for the rest. I would appreciate any better advise you can offer. Also, I am using epoxy grout but I have not grouted this section yet either.
I have two questions to ask.
First- I just installed another counter section ( The last section, Weehaa) with the 12×12 Absolute black granite tiles. I installed them Saturday morning using flexbond as my thinset over durock cement board. Somehow I missed a decent size flaw in the tile and I am not happy with it.
My second question- Same granite tile with epoxy grout installed. I took your advise using 511 impregnator. How often should I seal using this product. Also, Is it possible to seal tile too often? So far I sealed them twice just before grouting. I was thinking of sealing them again.
Again, I thank you for all your help and support.
Steve
Hey Steve,
Take a grinder and cut the big X in it from corner to corner and begin removing it from the center. Once you get the first part out it’ll be fairly easy.
The only thing that wears out sealer is abrasion. The need to reseal your counter is directly related to how harsh you are on your countertops. With regular maintenance you never need to reseal it. Really. It is, however, not really possible to seal it too much unless you get to the point where you have a very hard time removing the haze or film on top of it. You can seal it three times if you want.
Roger: In reading about grout lines, I have a question: I`m installing travertine on the shower walls and the tile has “rolled edges”……will this be a problem when it comes to grouting ? Does the thinset that may squeeze up between the tiles need to be removed just after placing the tile?
Thanks
Hey Chuck,
No problem at all. The grout lines will be a little lower than the face of the tile, at about the spot the edge turns vertical, but it’s not a problem.
You can remove the thinset whenever you want. It is MUCH easier to remove it before it cures.
I did a glass/travertine/marble mosaic tile (brick-layout, mesh backing) in my shower reno. Lots of the thinset came up through the grout lines. I intend on using a matching (white) grout, so how important is it to scrape out the thinset before grouting…. or can I just grout over everything and will it adhere to the areas where the thinset is…??? (It essentially looks like I’ve already grouted in many areas, but I haven’t….)
Hi Lynn,
From your description it sounds like you did use white thinset, yes? It is important to scrape them down to 2/3 the depth of the tile. Grout does not adhere to the thinset beneath it (it will, but not long-term), it adheres to the sides of the tile. You need to give it a surface to bond to. Since you did use white thinset you can probably get away with 1/2 the depth without any problems, but it does need to have exposed tile sides for the grout to bond correctly.