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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  • Jake J

    First query: I have Corian shower, with joints between the large pieces. Has been re-sealed every couple years with silicone based caulk, and within 3 months gets moldy. I have stopped having grout companies redo this as they did not seem to get enough of the old caulking out, so i have dug it all out myself. I am willing to pay for top of the line caulking, suspect it needs to be silicone, any suggestions on what brands would work best?

    • Roger

      Hi Jake,

      All silicone is essentially the same, it’s silicone. GE Silicone II is probably the best that is readily available.

  • Curtisb

    One thing I would not recommend anyone ever use (or at least any of us non-professionals) is Urethane grout. A contractor used it on our floors and shower (after having to redo standard cementations grout that they washed out the color from) and it was a nightmare. After firing them, it took us literally months to get all the plastic coating/haze off. It ended up requiring paint removal products which of course caused some damage to the actual grout lines which then required repair. The repair wasn’t easy as the product wants to stick to your application device more than it wants to stay in the grout line, can’t be thinned, etc.
    Whatever the theoretical benefit, the inability to have easy clean up, haze removal, and future repair is far far more burdensome.
    Not sure how Epoxy grout would differ but I would see the same issue if you tried to spread it out and didn’t get it fully off the surface before it set (vs. dried with the urethane).

    • Roger

      Hi Curtis,

      Thank you for your opinion. However, as a professional I disagree with you. Every issue you’ve stated above points to improper use of the product – period. When done correctly urethane grouts (and epoxy grouts) word VERY well. They just don’t install like regular grout. If you spread thinset on a wall, let it cure, then try to stick tile to it that won’t work either, because you’ve used the product improperly. :D

      • Dale

        I’m with Roger, as a do it yourself novice I used Star Quartz lock II urethane grout in our M-bath, floor, shower and tub surround with little difficulty. I followed the application instructions to the letter and had no issues what so ever after a year in use. I even used the urethane at plane changes, against the rules, but to-date not one corner grout line has shown signs of failure. I’m sure that’s because urethane’s flexibility allows for movement in corners. Its was expensive and you worked small areas at a time, but I’m tickled with the results. Also I have some left over ready for use in the event I have an issue. I’m totally convinced that Urethane’s are the wave of the future. I took a chance using this product as there were issues early in the development, but I’m a believer now.
        Roger I still think your intro should include Urethane’s as a separate class, like epoxy, as it truly is in a class of its own.

        • Roger

          You’re correct Dale, they are becoming much more a staple in the trade. I will update it soon, I wrote this when all the issues were happening in the first wave of them.

      • Curtisb

        Yes, you are a professional (though who admittedly has not worked with this urethane grout so cannot fully say what you do or don’t like about it – good item to review in the future). The issue is that many are not and even many who claim to be are not and only have dealt with challenges of standard grout (like the general contractors we hired who were a master of none).
        The issue is that for those who have not used this product and are not professionals, is that it is unforgiving relative to cementations products. If you do not fully get all of the material off you will end up with a very thin plastic coating that cannot be removed w/o chemicals like strong paint removers (which can do other damage). If you had a similar issue with standard grout, it is simple to remove and there are many over the counter products available everywhere to do so. The same is not true for urethane grout.
        So while yes, it could be very good, it is far riskier should you not do a good job of timely and super thorough cleanup. Hence the reasons that non professionals (and even professionals that haven’t practiced with the product first) should be wary.

        • Dale

          Curtisb, I see your concerns and I’m sure contractors who haven’t used urethane will get into trouble if applying like a sanded or unsanded grout. Many won’t work with epoxy for that same reason. I know in my application my labor was a good 25% more than had I been using regular grouts. But I felt the benefits outweighed the extra cleaning and smaller work areas before cleaning. Time will tell if the extra cost vs benefits are worth it. It’s my home and I wanted the best product I could find in terms of durability, stain resistance, flexibility and knowing I’ll never have to rework the grout lines again.

        • Roger

          I may have stated that I haven’t used them regularly. But I would have stated that over a year ago, as I have done so for the past year. I know what I like and don’t like about them. I know how they work. I know why people have problems with them and I know how to prevent them.

          The issue with any product used by people who are not professionals is that they can be used improperly. If the directions are followed this isn’t an issue. TEC urethane, for instance, can be cleaned up to three days later with GLASS CLEANER to get rid of haze. Hardly a ‘strong paint remover’. All brands that I have used or spoken to a rep about have a product, normally brand specific, that removes the haze (all over the counter, if you bought your grout over the counter). They are not ‘strong’ chemicals either. Urethane based products are fairly simple to degrade with the proper chemical, like ammonia, but are not necessarily potent chemicals.

          And if you’ve read around these people ARE weary of it, that is why they come here to ask questions first. The ones who don’t are the ones who should be wary.

  • Henry

    Hi
    I am planning to regrout a shower with epoxy and in the corners of the shower the tile edge on one side lines up with the polished side of the tile on the other side instead of another edge. Will the epoxy hold to this? Should I just use silicone instead? And is it out of the question to use epoxy group on the top of the tub along the tile walls?

    Thank you

    • Roger

      Hi Henry,

      You need to use silicone in all the corners as well as along the tub top. The acrylic will move at different rates than the tile and will create problems.

  • Brandon hatch

    Hi roger, I just installed 2×4 inch travertine mosaic tile in my shower floor. I filled everything with a light colored poly lend non-sanded grout as the lines we less than 1/8 of an inch. I have noticed that 1 or 2 spots on the floor grout where the grout color stays dark (wet look) when all the other grout stays true to proper color. Does this mean it is leaking? I put 511 impregnator on it (2 coats).if it is leaking, what should I do?

    • Roger

      Hi Brandon,

      Grout doesn’t leak. If your waterproofing is correct you don’t need to worry about anything leaking. As far as the dark spot it’s likely a spot where you did not get the grout line completely filled and there is a hollow spot beneath the grout (a grout ‘bridge’), or it is simply less dense there due to air in the grout mix. You can dig out that portion and regrout it.

  • Ab

    My tiler used sanded grout and the wrong color grout for my porcelain title
    For tile with a 1/16 gap
    Can it be changed out?

    • Roger

      Hi Ab,

      Yes, but it’ll need to be scraped out to at least 2/3 the depth of the tile, then replaced with new.

  • Riveter

    Is epoxy grout acceptable for 1/8″ grout lines on a super, glossy white, ceramic mosaic mini-subway tile? It is a thin tile. Also, would it be possible to use a large syringe or turkey baster to put the epoxy grout between the tiles? Can the epoxy grout be a glossy white?

    • Riveter

      Oops. And it is gor the shower surround above a cast iron shower pan.
      Thank you as always.

    • Roger

      Yes, it is acceptable, with a grout float. You’ll never get it in there with anything else, it’s a force thing, it’s made for that. No, it will not be glossy white, all grout is going to be matte.

  • M Kidd

    Spencer. Sounds like you and I used the same guy. I had the same problems with missing and crumbling grout, just days after the jobs completion. You have to call the installer back because you need the colour. The colours have match. When the person I used returned, he gave me a partial bag of grout and I done two further repairs on my own. Mix the grout with water into a peanut butter texture, then I just used my finger to fill in the gaps. Allow 24 hours to set.

  • Spencer

    Just had new shower tiles installed. Noticed guy didn’t get grout in between some of the grout lines. Grout done 4 days ago. Some small areas missing grout. Some areas not enough grout. Also hazy areas on my new tile! One more thing. He put bullnose around the edges but he didn’t grout the outer areas that meet the wall afterwards. It’s just empty. Don’t want to be bothered with this guy anymore. How do we fix this?

    • Roger

      Hi Spencer,

      You can go over it with more grout. It should be fine. The edge of the bullnose where it meets the wall needs to be caulked or siliconed, not grouted.

  • Michael

    After reading your reviews, I am going to use Spectralock in the steam shower I just built. I have done plenty of tile work, but never tried epoxy grout. Lowe’s only sells the mini packages. I am going to be grouting up near 170 square feet of tile. Can you tell me the most economical way of buying Spectralock? And should I be trying to find Pro or Pro Premium? They seem to be almost identical.

    • Roger

      Hey Michael,

      Pro and premium are nearly identical. They are for your purposes. This is where I get my spectralock: Spectralock epoxy grout.

      • Michael

        Thank you! I will order it tonight on this website. I used 6×6 tile and have 3/16″ gaps. The calculator, if I am using it right says it should cover 84 square feet per full unit. Is that correct? I am only questioning my math because the flooring guy at Lowe’s calculated that each full unit would only cover 44 square feet. If that is the case, I would order the commercial unit instead.

        • Roger

          Yes, you are correct. He is not (surprise!). :D

  • Don

    Nice site. So many helpful articles.

    Can anyone please tell me what I should expect with regard to coverage when grouting a river rock pebble shower floor? I have read that it takes more than you might expect, but for someone like me who doesn’t have a clue what to expect, that still leaves me in the dark. I have about 12.5 sq. ft. to grout, and I’m using Laticrete PermaColor. (FWIW, I used half a bag between the shower walls and the bathroom floor outside of the shower, but that includes a lot of waste as quite a bit dropped when I was doing the walls.)

    I split up the first bag into eight smaller portions, as I knew I wouldn’t be very quick to apply and clean. I have four of those smaller portions, or half a bag, remaining. If that won’t be enough for the shower floor, it seems like I should go ahead and dry mix and split up a second bag now, so I don’t have to do that in the middle of the job.

    Thanks for your help!

    • Roger

      Hi Don,

      You’ll likely use AT LEAST a full bag on that, probably closer to 1 1/2.

      • Don

        Thank you, Roger. Hopefully the 1 1/2 I have will be enough. Would I be wise to pick up an additional bag? It wouldn’t be the worst thing in the world if I was unable to finish the job at one time. However, my concern would be that the new wouldn’t bond well with the old if too much time elapses in between, so I’m anticipating that I need to keep going until the job is done, even if I do mix the grout in smaller batches so I have adequate time to clean the stones before it sets up too hard.

        Here’s another question, not really related to this article, but I’m hoping you can offer advice. We discovered that a few of the pebbles on the shower floor are loose. (I’m not sure why–maybe the thinset was too far gone when they were installed? We hand-placed some loose ones to fit around the drain.) What’s the best way to fix ’em?
        (a) Mix up a micro batch of thinset
        (b) Epoxy adhesive of some sort
        (c) Other?

        I’m leaning toward (a) mostly because I’m not sure whether it would be a good idea to introduce an unknown adhesive into the mix. I used Kerdi membrane, and I’m a little concerned the epoxy might damage it on the off chance some of the Kerdi is exposed in the areas I need to repair.

        Thanks.

        • Roger

          Hey Don,

          Just mix up a little thinset to reset those loose ones. It’s always a good idea to have more than you think you’ll need. Very cheap insurance.

          • Don

            Hi Roger,

            Thanks again for your help. The thinset seemed to work fine to reset the loose stones.

            I ended up using just under half a bag for the grout. Not sure if it made a difference, but I used what I think is a somewhat unconventional technique. Rather than a float, I used a gloved hand to spread the grout. Palm worked well for spreading, side of palm for squeegee, and fingers worked well for ensuring the grout got down into all of the nooks and crannies. (Hmm. Suddenly I feel like an English muffin!) The whole thing actually went much easier than I anticipated, and we’re happy with the look. We’ll see how well it drains once everything else is wrapped up!

            Thanks for your help.

  • liz

    So glad I found your place. Despair!! This man that installed my slate tiles, turned out to hire someone to do the job, they butt the slate–happened two days ago. There are some lose tiles (counted 4 on a 120 square feet; about 4 broken) but they are not even. What can I do? Is it possible to grout? Perhaps using epoxy or spectral lock. I’m afraid I won’t be able to wash that area (fear of mildew–even though I live in Nevada–not to mention the risk of those tiles coming up loose). I suspected he didn’t know anything about tiling so I told him that I had placed a question on the internet to see if slate could be butt but he was very pushy and I never got the answer from that site either. So I got tired and said “yes” go ahead. How big of a problem is this? Thanks

    • Roger

      Hi Liz,

      It’s a big problem. Butting grout joints. It really needs to be removed and replaced correctly, that floor is not going to last. Sounds like it’s already coming apart. No kind of grout will save it.

  • Bill

    HAVE A CUSTOMER GROUTING A FREEZER AND HIS CUSTOMER CAN NOT TURN THE FREEZER OFF NEED TO GROUT WHILE FROZEN IS THIS EVEN POSSIBLE?

    • Roger

      Hi Bill,

      It can be done with epoxy grout, it’ll just take longer to cure. It is usually fully cured in 48-72 hours, but that time frame can vary wildly.

  • David

    I’m sold on using epoxy grout. Will be using SpectaLock for all the floors. I have one issue/concern. The kitchen backsplash is a mix of stone and glass in 12×12 mosiac sheets. Since SpecraLock is sanded, I am concerned with scratching the glass. I want the stain resistance/prevention in that area as much as the floor. Thoughts? Options? Thanks!!!

    • Roger

      Hi David,

      Always test first, but I have yet to see a glass tile that spectralock will scratch. Doesn’t mean it won’t, just means I’ve never seen it, and I’ve installed a metric shit-ton of glass tile with spectralock. :D

  • Rob R

    my bathroom walls are white 3×6 tiles from Lowes, laid tight in a subway or brick pattern. I want as low maintenance as possible, so am looking hard at Spectralock in Brite White.

    my question is on the finished appearance…is it a creamy smooth caulk like appearancd, or is it a sanded grout appearance?

    • Roger

      Hi Rob,

      In grout lines that size it would be a smooth finish.

  • Jeff

    What do you think about using the Spectralock expoxy grout bwtn tile and wood floor instead of caulk? I did a previous floor using Avair tile (Snapstone) their flexible grout and it has held up for 3 years with no cracking.

    • Roger

      Hi Jeff,

      The grout will not crack, but there will be a crack between the grout line and the wood eventually. The wood will move, the grout will not. It won’t work, you need to use silicone.

  • Dustin

    I believe that it is the mess mat that is under. I am not the one who installed and I am not going to be installing. I work at a hotel, so I have inherited all the problems that are caused by everyday use plus whatever problems are arising due to cutting corners when they were remodeling. :bonk:

    • Roger

      Hi Dustin!

      As you did not reply to a previous thread (as stated right above where you typed this answer), where I assume you asked a question and I asked one right back, I have absolutely no idea what you may be talking about. :D Sorry.

  • leticia munoz

    I had granite put in my kitchen and they used latex grout in some areas and I don’t like it. it comes through the black granite. How do I remove this safely and can I re-grout with epoxy grout? Is epoxy grout water resistant?

    • Roger

      Hi Leticia,

      I don’t understand what you mean by ‘it comes through the black granite’? And latex grout is both a) Not a thing and b) encompasses nearly every modern grout on the planet. I need to know what specific grout they used.

  • Karen

    Oops I meant my post for Roger! Also, I have only done 4 tile jobs before and want to know if epoxy grout is something I can DIY .

  • Karen

    Hi Kathy, I have a large walk in shower I am DIYing and to save money want to use 12x12s on the walls. Will this be a problem and what size grout lines should I use? I have already installed the same 12x12s for the floor and used a 1/4 in grout line there.

    • Roger

      Hi George,

      Yes, you can use the 12×12’s on the wall as well. You can use whatever size grout line the tile will allow. I normally do 1/16″ on walls, but you can certainly go larger if you wish.

      ~Kathy :D

  • bill

    Hi there. I just finished using sanded grout on my backsplash in my kitchen. I happen to have had a bit of it fall into my granite sink and has left white stains in my dark brown sink. Is there any type of cleaner that you know of that help clean this up in my new 600$ sink? I have tried nylon scrubbing pad and steel wool very carefully but they are not coming out!!!

    • Roger

      Hi Bill,

      I would contact the manufacturer of the sink, they should be able to give you detailed instructions.

  • Henry

    Hi Roger,
    A while back I installed about 400 sf of floor tiles in my house with 3/16″ spacers, and the grouting process (sanded grout) went as smoothly and easily as I expected. Then I tiled the walls in a bathroom with 4″ tiles without spacers (other than the “tabs” on the edges of each tile). I grouted them with polyblend unsanded grout, and I have never had a more miserable DIY time. If instead of grout I had spread a tube of acrylic caulking with a putty knife, I don’t think it would have been any different. I used a good scale to weigh the correct water-cement ratio, and followed the instructions in the box religiously. After 5 minutes of starting, the first grout I had spread was a thin sticky film, and after 10 minutes the float could not wipe away the grout on the surface. I ended up working on 10 sf at a time using more water in the mix than prescribed, and had to press so hard with a pretty wet sponge each time in order to remove the excess grout, that many of the joints ended short of grout. How do you recommend I finish filling those joints?
    Now I want to tile the walls in my other bathroom with 6″ tiles and am thinking of using 1/16″ spacers and sanded grout. What do you think?
    Thank you.

    • Roger

      Hi Henry,

      Mix up some grout fairly wet (more water than called for) and go over the walls again. Let it sit for about fifteen minutes then wipe it off. That should fill the spaces for you. You could go with the spacers and sanded, or you could just use an unsanded grout that is NOT polyblend. :D

      • Henry

        Thank you, Roger, you are very kind. I think I’d rather get a good tooth pulled out with pliers and whisky than using that polyblend again.
        The other big DIY store sells Laticrete, Snapstone, Bostik and Mapei grouts. Do you recommend one over the others?
        Can I use epoxy or urethane grout over my existing polyblend grout in those places where the joints ended up short of grout?

        • Roger

          If you use epoxy or urethane you’ll need to remove the existing grout down to at least 2/3 the depth of the tile for the new grout to grab correctly and last. I prefer laticrete over everything, mapei is also very good.

  • Yakov

    Hi Roger,
    I installed 12×12 porcelain tile and I used 1/16 spacers.
    But some tiles together make v shape and space between seems 1/16 -1/8.
    Can use Unsansed grout or Sanded.
    I want to use Laticrete 1600 unsanded grout, can I ?

    Thanks

    • Roger

      Hi Yakov,

      Yes, you can.

      • Yakov

        Thanks Roger,
        One more question, what do you think about PermaColor grout. I spoke to Laticrete tech support the recommended PermaColor instead Unsanded 1600.

        Thanks.
        P.S.
        tile 12×12 porcelain.

        • Roger

          Great stuff!

  • Pam Wollenburg

    I have been trying to fine the answer to my concern. I am remodeling my bathroom. I want to make a walk in shower. The bathroom is on the main floor with a finished basement below. I am concerned about a leak from the shower to the basement. I want to make a walk in shower and I have looked at shower bases that are all one piece so that seems safer to avoid a leak. BUT I really like the look of tile I have not talked to anyone about doing the work yet, I want to do the research before I talk to the remodeler. Is it safe to have tile floors without leaking and what should I make sure they do. also what do you think of epoxy grout. Is it worth it. Thank you for your time.

    • Roger

      Hi Pam,

      Absolutely it is, I do it all the time. See what waterproofing method they use on the shower floor, then check the site for information about it. All proper methods work just fine, provided they are correctly installed. Feel free to ask any questions you need to in order to make an informed decision. I do think epoxy grout is worth every penny, and then some.

  • Kathy

    I need your help! I read every post on this site and am now thoroughly confused on what to use in my bathroom. I am not a fan of grout anywhere, it’s hard to clean and high maintenance. I am too old to use the bleach and toothbrush. We are replacing a 40 year old bath floor with Style Selections Metro Wood Walnut Glazed Porcelain Floor Tile (Lowes). 1) Is 1/16 grout line too small? 2) I read Snapstone grout in bark color looks amazing. Never heard of it. Can Snapstone grout be used with porcelain tile? 3) What brand name grout do you suggest we use that has least amount of maintenance?

    • Roger

      Hi Kathy,

      1. 1/16″ is just fine provided you have flat substrates.
      2. Snapstone grout is not a product used for regular tile, it is for snapstone, a laminated product. If you want easy maintenance use spectralock epoxy grout.

  • Dave

    Roger,
    We are nearing completion of our bathroom redo. Our field of 1″x2″ polished Carrara mosiac subway floor tiles have really thin joints ranging from almost nil to approx. 3/32″. Seems like you would recommend unsanded grout for this condition.

    The 6″x12″ honed carrara border tiles have a 1/8″ joint. If we use unsanded throughout, are we going to be struggling with shrinkage at the border joints? I really don’t want to try to use both sanded and unsanded. I’m fearful that sanded will scratch the mosaics unless we spend time masking. Is that masking idea even realistic?

    I really appreciate all of your advice. What a great service.

    • Roger

      Hi Dave,

      I would actually use sanded for all of it. Test the sanded on our marble, but it actually shouldn’t scratch it. If you decide to go with unsanded in all of it (which you can) just go over the larger joints a second time about three hours after the first to ensure it’s packed in there well and the joints are full.