There are three basic types of grout available for your tile installation. They are:

  • Non-Sanded (also known as Unsanded)
  • Sanded
  • Epoxy

Choosing the correct grout for your particular installation will not only complete the job correctly, it will also cut down on maintenance. Properly installed and sealed grout will last for the life of your tile. So which to use and when?

Non-Sanded (or Unsanded) Grout

Unsanded grout is made specifically for grout lines smaller than 1/8 inch wide.  This is a general rule. I use unsanded grout only in tile with grout lines smaller than 1/16″. Unsanded grout (all grout to different degrees) will shrink as it cures. The reason for only using it in smaller grout lines is the wider the grout lines, the more grout must be used to fill them. The more grout you have, the more it will shrink. If you try to fill grout lines that are too large the grout will shrink enough to pull away from the sides of the tile.

Unsanded grout is easier to work with, especially on vertical surfaces such as a shower wall, because  it is “stickier” than the sanded variety. You can spread it onto the wall and it will stick there while you force it into the grout lines. It is also much easier on the hands than sanded.  Although it is easier to work with, you need to make sure that the application for which you are using it is correct.

Sanded Grout

Sanded Grout is used for any size grout lines 1/8″ and wider. Although the specifications state unsanded grout be used in grout lines that are exactly 1/8″, you really should use sanded for them. It will ensure proper adhesion to your tile and guard against too much shrinkage. No, not Seinfeld shrinkage, grout shrinkage.

Sanded grout has fine sand added to it. This prevents the grout from shrinking too much as it cures. That’s why it is used for larger grout lines and should be used for the majority of tile installations.

If you have a polished stone such as granite, marble, limestone, and some polished travertine, you should be careful about using sanded grout. While sanded may be the correct choice for the size of grout lines, it may not be the best choice. Depending upon the polish of the stone the sand in the grout may actually scratch it. If you decide to use sanded make sure you test it in an inconspicuous area first to ensure it will not scratch your finish. Or use epoxy which would be a better choice anyway.

Epoxy Grout

Epoxy grout is the top of the line and best choice for any tile application. It can be substituted for sanded or unsanded grout.  It is more sturdy than both as well as being waterproof and stain resistant.

Epoxy is a two or three part chemical consisting of the base and the activator. With some brands the color is an additional part that must be added. Once the parts are mixed a chemical reaction begins. From that point, depending on the brand of epoxy, you have only a limited amount of time to get everything grouted before the grout becomes stiff enough to be unworkable. When it reaches that point, if you do not have everything grouted you are SOL.

To help slow the cure time you can mix your epoxy then put half of it in the freezer. The cold air will slow the chemical reaction and lengthen the working time. You can then work with the other half until it is all used. Clean it up, wipe everything down, then grab the second half out of the freezer and finish up. When you first pull it out of the freezer it will be, well, frozen. It thaws quickly, though, so should be workable within a few minutes. This essentially doubles the working time of your grout and ensures you don’t have to rush through it.

Since most epoxy grouts do not contain sand (or at least not in the classic sense of sand) it will normally not scratch your tile. If you have highly polished granite or marble that’s important. Be sure to test first anyway!

Different brands of epoxy have different working times as well as some being more difficult to work with than others. The brand with which I have had the most luck and the only brand I ever use is SpectraLOCK from Laticrete. It has a longer working time than any other epoxy grout (at least any I’ve ever used) and is virtually stain proof. Please don’t take that to mean the you can grout a jacuzzi with it, fill it with cherry kool-aid, and expect it not to be pink (Don’t do that). It just means that for all intents and purposes it will not stain without concerted effort. In my opinion it is the best on the market.

The only drawback of epoxy grout would be the price. It is fairly expensive. When weighed against the upside, however, it is well worth it. Low maintenance demands and high durability of epoxy grout make it well worth the money.

Picking the correct grout for your application is a key part of a proper tile installation. If you choose incorrectly you could end up with a multitude of problems and headaches. Grout, chosen and installed correctly, will complete your tile installation and push it from a good tile job to a great one. Do not underestimate the power of the grout.

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  • Randy

    I have bad hands and can not force the grout in easily. I want to use epoxy grout and thought I could do small batches and a powered caulk gun. I have a 3/16 to 1/4″ spaces. Any ideas? Love your page & book!
    Thank you!
    Randy

    • Roger

      Hi Randy,

      A grout bag would be a better solution is you have to go that route. A powered caulk gun isn’t going to do much, especially with grout lines that large.

  • Greg

    Hi, Great info on your site – Thanks
    I am about to grout the shower floor. I have 2″ tiles with approx 1/16″ spacing (over Schluter waterproofed system). I have purchased Polyblend non-sanded grout. I am wondering if I can/should mix an epoxy with it. Also, if I do use an epoxy, should I caulk at the floor/wall connection? Caulking would hide the slight imperfect tile cuts on the bottom row.

    Thanks

    • Roger

      Hi Greg,

      You don’t mix regular grout with epoxy. Epoxy is a specific type of grout, not an additive for regular grout. Mix it with water or custom’s admix for grout (it’s latex based) and silicone the changes of plane.

  • Andy

    Our contractor used 2X2 porcelein tiles which come in a mesh on our bathroom shower pan. The shower pan is a Schluter shower base. I know that he used sanded grout. The grout has come out in many parts of shower floor. How do we fix this?

    • Roger

      Hi Andy,

      It depends on why the grout is coming out. Is there orange kerdi membrane over the shower base beneath the tiles? Are the tiles getting full coverage of thinset to bond to the pan? You’ll need to remove one or two of the tiles to determine the underlying cause.

  • Bill

    Hey Roger
    I am installing a glass tile mosaic outside on a horizontal concrete pad.
    I have used mega lite thin set and I am going to grout with Fusion Pro. The grout lines vary between 1/8 to 1/4″. Do you see any problems with this approach.
    Thanks for your help.

    • Roger

      Hi Bill,

      Other than having a glass mosaic in an exterior horizontal application, no, I don’t see any problems with the mega lite or the fusion pro. :D

  • Alex

    Can I add sand to unsanded grout to make it sanded so I can use it with bigger grout lines? I have a few packages of unsanded grout left and I don’t want to waste them. Thanks

    • Roger

      Hi Alex,

      No. It is not regular sand.

  • dave

    dear floor elf,
    we are trying to determine what kind of grout we should use in our bathroom. We are using slate for the shower floor and some of the grout lines will be 3/4

    • Roger

      Hi Dave,

      3/4″ grout lines??? Really? You need sanded grout, but you may need to do it twice, once again after an initial cure.

  • Kelly

    Hi there,

    I’m preparing for a shower surround tile installation. The field tile is 4×4 with 3/16 grout lines. The accent tile is two bands of 1″ mosaic with 1/16 grout lines. I am wondering, if by using sanded grout for the larger tile spacing, will I run into any problems trying to set sanded grout into the small mosaic spacing. What do you suggest?

    Thanks!

    • Roger

      Hi Kelly,

      You can use sanded grout for all of it.

  • brian

    Im doing a custom shower (floor and walls) and am thinking about using epoxy grout, will it be waterproof? Worried about it leaking.

    • Roger

      Hi Brian,

      It will be if you put a waterproof substrate behind it. The tile and grout are not the waterproof aspects of your tile installation, the substrate it. It should be completely waterproof before you even open a box of tile.

  • Jerry

    Hi Roger, I’m using decorative very light green glass (1″x2″) tiles as part of a waterfall decorative band on a shower wall, which is using white subway tiles. My intent is to use a white mortar, and was looking at using a light grey grout.

    Should I be concerned about using sanded grout?

    Also, any tips or suggestions for dealing with mortar and grout applications if the glass is slightly thicker the the subway tiles?

    Greatly appreciate hearing your thoughts.

    Thanks for keeping a really helpful resource page.
    Jerry

    • Roger

      Hi Jerry,

      Sanded grout shouldn’t affect the glass, but ALWAYS TEST FIRST! Use a smaller v-notch trowel for the glass and a larger for the field tile to even them out.

  • Rick

    I’m installing slate tile with very thin gout lines. For thin lines it’s recommended that you use non-sanded grout, but other articles I’ve read say you should use sanded grout with slate. What do you recommend for slate tile with thin grout lines?

    • Roger

      Hi Rick,

      If you have 1/16″ grout lines or smaller use unsanded, if they are larger use sanded. The type of tile or stone makes no difference at all.

  • Carrie

    Roger;

    I am a mosaic artist that does large-scale interior and exterior installations. I normally use a sanded grout because I like the workability and flexibility of it since my grout lines are often of varying widths. I just used Laticrete’s permacolor grout on an exterior quarry tile walk. I had a couple of issues with it that I wondered if you have experienced. First, the color was much lighter than the grout swatch. It was close while wet, but once it dried, it was considerably lighter. Is this common with their products? Also, I found that some batches went on and wiped of just fine, while others stuck mercilessly to the tile (we sealed the tile prior to installing the grout because quarry tile is so matte and rough). Any thoughts on why I had such inconsistencies? We measured the water every time and followed the directions to the letter. Thanks!

    • Roger

      Hi Carrie,

      Quarry tile is a whole different animal, that is likely what is causing your problems. I have never had inconsistency issues with laticrete grouts. Quarry tile, although you sealed it (the top) is still a VERY porous product. The sides of the tiles (I assume you did not seal those) will suck moisture from the grout as soon as it hits the joint. Quarry tile should either be sealed completely before installation (sides as well as the top) or you should soak down the tile with water immediately before grouting.

  • Shelia

    What is the best grout for porcelain tile flooring? Would really like one that we don’t ever have to seal. Thanks.

    • Roger

      Hi Shelia,

      Tec power grout would be a good option for your installation.

  • Brenda

    My contractor used the wrong color sanded grout on my polished marble floor tile. Rather than tearing it out and installing new tile, he says that he can change the color of the grout using “power grout” on top. Is that true?

    • Roger

      Hi Brenda,

      No, not on top. The grout needs to be removed to a minimum of 2/3 the depth of the tile first.

  • brandi melton

    I am doing a shower in waterfall dream glass tile with a symphony bubble band around the shower what grout would u recommend for installation??? And any other tips???

    • Roger

      Hi Brandi,

      I would use whatever grout the glass manufacturer recommends, as well as whatever installation technique they recommend. There are SO many different types of glass tile that the only way to ensure a successful installation is to speak to the manufacturer first.

  • john

    Do you have a favorite sanded grout brand?

    • Roger

      Hi John,

      I like laticrete, tec and c-cure.

  • cynthia ramsay

    Hello Roger Elf,

    I am spending a lot of money putting in beautiful fill tile in the tub surround, (off white with a highly polished finish and red glass pencil tile for a six inch border). The tile man, the tile store, the GC, and I are at a crossroads about what type of thinset and grout should be used behind the very thin glass pencil tile that will be used as a border in the shower and back splashes. Also, the pencil tile’s depth is different from the field tile by a good quarter of an inch. Two questions: What will bring it out to be level with the field tile and what do we use to adhere it and then grout it. Whoops. That’s three questions. Thanks so much for settling this.

    • Roger

      Hi Cynthia,

      Thinner inserts can be built up with several methods. Modified thinset and the regular grout will work just fine. I’m not too sure why there is a discussion about it? Is there something in particular someone is worried about?

  • Neil

    I have a slate floor in a old house and the grout is starting to come out what do you suggest I do to repair the grout

    • Roger

      Hi Neil,

      You need to find out why the grout is coming out. It is normally indicative of movement somewhere beneath the tile, which means the substrate needs to be rebuilt or built properly.

  • Patty

    Can a white marble shower that was grouted with non sanded grout be regrouted using epoxy grout? I has already been done 2x with non sanded and is constantly staining. The only problem is that we will not be able to get 100% of the old grout our because the marble is very soft and porous and tends to chip easily.
    Thanks

    • Roger

      Hi Patty,

      Yes, it can. But you’ll need to get the grout down to 2/3 the depth of the tile before regrouting.

  • Debbie

    I have small 2×2 tiles on my shower floor. The grout in a few places is cracking – shower is 12 years old. The grout was bone.
    How should I attempt to fill the cracks and with what type of product.

    Thank you.

    • Roger

      Hi Debbie,

      It depends on what is causing the cracking. If it’s purely a grout issue you can try to just grout over it, which would fill the areas. If it happens again it is indicative of movement of some type and a deeper underlying issue.

  • Jeff

    Mr Floor Elf I really need your help. I installed backsplash marble mosaic tile and before grouting I sealed the whole thing. I used sanded tec power grout and followed all instructions. So far everything went ok… but after the final clean up I realized that the marble lost its original sheen and everything looked dull or opaque. I let it dry and I tried to do a more meticulous clean up but to my surprise the damage was done. Is there any way that I can restore the original sheen to the mosaic tile? Thanks and waiting anxiously for your response.

    • Roger

      Hi Jeff,

      You can buff it. Just like a car, with an electric buffer, but you don’t use any chemicals or wax. You can use sealer when buffing.

  • Craig

    can I use caulk for all my grout lines, is this an expense thing why not to just caulk or just a bad idea all the way around.

    thanks

    • Roger

      Hi Craig,

      No. Caulk is not a permanent product. It will lose elasticity over time and pull away from the tile. I’m sure you’ve probably seen the results of that around the bottom of a tile wall in a tub – it grows all sorts of nasty stuff. It can be easily replaced in the changes of plane, as it should be, do you really want to do that every 5-7 years in your entire shower? :D

  • john

    Roger, Is Fusion Pro any good?? What are your favorite uerathane grouts?

    • Roger

      Hi John,

      I prefer technicolor by tec (it’s actually acrylic-based) and Laticrete plasma. But fusion pro is also very good, I’ve used it a few times.

  • Kay

    Any reason why I can’t or shouldn’t use an epoxy grout on my 3″ polished marble hex tile, over Ditra Heat? I can’t seem to find anything saying no on the internet, so that must be the case right? And any thoughts on what size trowel for laying? 3″ is between a lot of the recommendations I see for a 2″ or 4″ tile – which side do I err on?

  • Rose

    Thank you! I wanted the epoxy after reading but it was a 14 day special order and I didn’t give myself enough time. The epoxy was 15lbs and it was $119 and the unsanded was $12 for 10lbs. Hope that helps others! Order ahead.

  • Marissa

    Hi Roger- your site has been so valuable to me in my remodel- using your instructions I built my own 6ft x 4ft walk in shower starting at the subfloor! I wouldn’t have been able to do it without all of your instructions especially for how to mix & install my deck mud, waterproof membrane, & build my curb!!! I read dozens & dozens of how tos online but every other guide left out huge important steps and were far too vague for someone w/ zero prior knowledge.
    I have 2 questions for you today
    1) how many people have asked you how to waterproof their tile & or grout???? :bonk: :bonk: You are too kind for your continued efforts to repeat hundreds of times in your various threads where the waterproofing happens!!!!
    2) I have a floor that I tiled & have only partially grouted in an area that is rarely used & thus the priority to finish went to the bottom of the to do list. I am going to finally complete the rest of the grouting. Where I last grouted is obviously cured, the ends of the dried grout is nearly vertical in the tile space (maybe a 70degree slant). The joints are 3/8″. Where I put the new grout will it cause any issues at the transition where the new grout meets up with the dried finished grout? To be clear I did not half fill my joints- I completely filled 25% of the room’s tile joints with grout & did not grout the other 75% of the tile joints. Thanks so much!!!

    • Roger

      Hi Marissa,

      1. I’ve honestly lost count. I could type that response if I were in a coma, I think. :D

      2. I would scratch out the ends to expose presently unexposed grout in the existing lines to ensure a good bond. The angle doesn’t matter, just that you are going to presently unexposed grout.