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tuesday22

sanded grout? unsanded?

tuesday22
15 years ago

I've read everything I can and I need clarification.

In one post, this explanation for choosing sanded/unsanded grout:

The ONLY thing that determines which grout should be used is the joint size. NOT the glaze, NOT aesthetics, NOT the material (ceramic vs. glass or polished marble), NONE of those. I'll repeat-- the ONLY thing that determines which is used, is the joint size. Anything under an 1/8" takes unsanded grout. Anything 1/8" or bigger, you use sanded grout.

But from another forum:

Ceramic mosaics get grouted with sanded grout. Period. Unless you want to regrout later because of pinholes, shrinkage and cracking.....and hoping you don't have to grout a THIRD time.

(For a bit of reference, the discussion was regarding what to use for 1/8" joint...which seems to be right on the edge of both sanded and unsanded guidlines.)

My wall tile (which goes around the shower) is 16"x16" polished, my floor is unpolished 2"x2", and all joint are just a tiny smidge over 1/16".

So the walls can go unsanded (clear enough), but what to do about the mosaic on the floor? The gap dictates unsanded, but being mosaic might possibly perhaps suggest sanded.

Please, any clarification or guidance would be very appreciated.

Comments (24)

  • bill_vincent
    15 years ago
    last modified: 9 years ago

    Let me ask you-- are both stone?

  • tuesday22
    Original Author
    15 years ago
    last modified: 9 years ago

    Porcelain, actually.

  • bill_vincent
    15 years ago
    last modified: 9 years ago

    The 2x2's I would definitely use sanded grout for. As for the wall tile, you're right at the line. I think I'd probably use a stiff mix of unsanded grout, only to try and keep the stone look I'm sure you're going for.

  • tuesday22
    Original Author
    15 years ago
    last modified: 9 years ago

    "Stiff" because otherwise it will slump down the wall? Or for another reason?

    And what is it about unsanded that gives porcelain more of a stone look? And wouldn't I want that same aesthetic for the floor? (function nonwithstanding)

  • bill_vincent
    15 years ago
    last modified: 9 years ago

    Stiff because otherwise, it'll shrink and crack. It's not the unsanded grout per se that gives porcelain a stone look. It's the fact that with real stone, that joint would be unsanded, hands down. The mosaics are a different story. Those would still be sanded.

  • tuesday22
    Original Author
    15 years ago
    last modified: 9 years ago

    How does the sanded grout fit into the little joints on the floor? I thought small joints NEEDED unsanded because the sand wouldn't fit?

  • bill_vincent
    15 years ago
    last modified: 9 years ago

    You work it in with the grout float. Because the joints are so shallow, it doesn't take as much to fill them, so the joints don't have a chance to get clogged.

  • tuesday22
    Original Author
    15 years ago
    last modified: 9 years ago

    Well, okay, but the mosaic joints are exactly the same depth as the wall joints. (The little 2x2 squares were actually cut from an unpolished version of the big wall tile.) That is to say, they are both 5/16" deep.

  • tuesday22
    Original Author
    15 years ago
    last modified: 9 years ago

    And two adjoining questions:
    1.) Just curious, but WHY do you change the rule (size of joint absolutely dictates type of grout) for mosaics? And is the rule changed for mosaics on a wall? (Mine are on the floor.)

    2.) How do I find examples/pictures of grout that is "full," standard, or too low? I've looked and googled everything I can think of, but I haven't been able to find any pictures or examples. (I read that unsanded grout could shrink in the joints more and I want to find what the visually looks like. And what normal looks like. And how to maybe get fuller joints - though obviously there will always be some depression.) Why is this not more documented on the vast world wide web? Isn't there an industry standard of some quantifiable amount? Wouldn't that be a visual reference point?

  • bill_vincent
    15 years ago
    last modified: 9 years ago

    1) because experience has shown me that although either one (going by TCNA's rules) can be used for mosaics, unsanded grout will tend to shrink too much and leave pinholes, so for any kind of mosaic, be it ceramic, glass, or stone, I'll always used sanded grout. You can use anything you like.

    2)

    Why is this not more documented on the vast world wide web?

    Good question- one that I can't answer.

    Isn't there an industry standard of some quantifiable amount?

    There is, although I can't find it right now (just looked in the ANSI Book and couldn't find the spec), but it basically reads that the grout should come up to the edge of the face of the tile and be just a bit concave.

    Wouldn't that be a visual reference point?

    I think I've already answered this, but just in case, can you clarify that a bit?

  • tuesday22
    Original Author
    15 years ago
    last modified: 9 years ago

    Thank you. That was very explanatory. When I asked "why," it was not to question you or doubt the information, but rather just curious. Maybe it is my inner scientist, but I always am curious when apparent "rules" change under certain circumstances. Tile has a LOT of science (chemistry, physics) involved in its successful installation and continued ability to perform as a surface without compromise, so....
    Yeah, I was curious how the size of the *tile* would affect the curing and solidity (or whatever metric) of the *grout.*

    It is still interesting that this is so. (I didn't mean to imply that that is the same as doubting the answer.)

    Thank you for the drawings. We've never had tile so I've never closely looked at grout before, and unfortunately, have no well-executed examples to study. I didn't actually mean to suggest that you are now responsible for all the content of the entire internet; I just thought that maybe I missed what to search under.

    And I should have editted most of #2. The rifle of questions was a lot from from frustration on my part failing to find any kind of visual reference point for grouting standards. I think the "visual reference point" thing was just part of the failed-to-find-any-kind-of-photos-illustrating-acceptable-grout-levels thing. I feel more comfortable if I know what *should* happen with contractors. Again, my apologies. I should have clarified that the "missing" internet reference and non-existant internet images of industry standards would - theoretically - serve as "visual reference" for people trying to, well, have a visual reference point of the grout depth standards.

    I didn't mean offense. I was just trying to learn what was what.

  • bill_vincent
    15 years ago
    last modified: 9 years ago

    I'm not taking offense. I actually consider your questions a challenge, and very well may incorporate parts of this thread into the FAQ thread on the gallery side of this forum, as well as an FAQ that I'm putting together and editing right now for my own website.

    One thing I've found in this industry is that many of the rules will cover MOST situations MOST of the time. Unfortunately, as many in the trade will tell you, NO ONE in this trade knows it all. I know two people who come close (in the entire industry!), but even they can learn from the rest of us. Most of what I've learned, I've done so through experience as well as listening to what my father and the craftsmen he had show me the trade had to say. There were, for the most part, 6 guys who taught me the trade, everyone of them, Italian Americans who came over from the old country (as did my grandfather), and used every bit of patience they had to teach me their craft. You think you're testing MY patience? You shoulda seen what I did to THESE poor guys! In addition to asking the same kinds of questions, they had no choice but to deal with me because I was the boss's son! I remember when I first got out of the Navy and started working for my father, one of these guys one day asked me straight out-- "When you was a little kids, you was sucha nisa boy. Whah happened?" God bless every last one of them.

    90% of the time, I can tell you why things are the way they are. For that other 10% of the time, I can still tell you what has to be done to make it work, and I'll tell you I don't know why, but I DO know that's the way it has to be.

    See, I'M still learning, too-- even after 29 years full time in the trade.

  • tuesday22
    Original Author
    15 years ago
    last modified: 9 years ago

    I'm glad I didn't offend or annoy you. It wasn't my intent.

    Learning is good. I can't stand people who get a big attitude of I've-been-doing-this-for-X-number-of-years and take mortal offense. I especially can't stand it if they're wrong (which can happen to us all sometimes) and still have the big 'tude.

    So I've been reading about the actual mechanics of grouting. I'm not sure I actually understand it but I think I get the gist. BUT, how do you use the flat thing over the little mosaic squares? How do you wipe the excess off without smashing over the joints? How do you wipe down the haze without messing up you smooth and WET grout?

    And is there any trick for obtaining a fuller joint? Is there any reason I would NOT want that? (I would think it would be a bit easier to clean, easier to sweep, wouldn't need actual mopping so often.)

    Europeans are, in my experience, pretty okay with "the boss' son" idea. (We lived there while my husband was stationed in Brussels and then Stuttgart.) Nepotism is pretty common over there, compared to here, for better or worse. (I read an article in IHT about how 25% of kids in Europe go into a parent's profession - though not necessarily the same company - and the number is around 1% for us. The article was talking about "heritage expertise" which is sort of a version of "institutional memory," and mentioned the bodies of knowledge that still live through the kids, while it is measurably dying out where nepotism isn't so common, like here.)

    I like your rendition of the Italian accent.

    I've always been fascinated by areas of expertise that have very little written down. Sure, the ANSI thing gives guidelines for finished product, but no methods to actually accomplish that. Tile setting MUST be handed down. I guess I put woodworking in that category, too. Sure there are some books, but in the end, the body of knowledge lives almost primarily in the ones who actually execute the task. Unlike, say, chemistry or something that is VERY well documented, where all the living chemists could die tomorrow and we'd all still know how to titrate.)

    (Weirdly, I'd put computers in with tile and woodworking. Think about it: how does everyone learn the tricks and work-arounds to computer quirks and programs? Usually from someone else that somehow figured it out or they learned it from yet another person. Yeah, you can take a computer class, but does that actually make you proficient any more than taking a tiling class at HD make me into you?)

  • bill_vincent
    15 years ago
    last modified: 9 years ago

    BUT, how do you use the flat thing over the little mosaic squares? How do you wipe the excess off without smashing over the joints? How do you wipe down the haze without messing up you smooth and WET grout?

    I can answer all those questions with three little words:

    Diagonal to the joints.

    When floating, the float (flat thing) acts as a heavy duty squeegee, pushing the grout into the joints, and cleaning off the heavy excess grout from the face, in one swipe. However, of that float were to be used parallel to the joints, obviously it would end up going INTO the joints, thereby digging them out. If you pass the float diagonally to them, then it passes smothly over the top, depositing the grout into the joints, screading them off flat, and cleaning the face of the tile. Same when washing the tiles afterward. Your first wash to loosen up the grout on the face and shape the joints should be with somewhat light pressure in round motions (think Mr. Miagee and "sand the fence"). Once the joints are uniform and the grout on the face of the tile is loose, the sponge gets rinsed well, squeezed out as much as possible, and then two swipes, diagonally. The first, removes the majority of the excess grout, flip the sponge, and now you use fingertip pressure, so the sponge doesn't touch the joints any more than necessary and you clean the tile the rest of the way. Then rinse the sponge again, and move on in the same manner, until the whole floor is clean. Now, it's rare that the floor (or wall) will be completely 100% streak free when you're done. However, the streaking should be light enough where hitting it with a mop and water the next day should be enough to remove it.

    And is there any trick for obtaining a fuller joint? Is there any reason I would NOT want that? (I would think it would be a bit easier to clean, easier to sweep, wouldn't need actual mopping so often.)

    There's only one way I know of to get a joint completely full, flat, and flsuh to the surface of the tile as in the first joint in the drawing above, and I'll bet that 90% of the PROS today have never even heard of it, much less anyone else, and that would be instead of using s sponge to clean the grout, you'd use dry grout and a burlap bag to rub the face of the tile (this would also fill the joints flush), and then clean the face of the tile with dampened sawdust. Problem is that usually, using this method the tile then has to be acid washed, and aside from the fact that very few homeowners are qualified to use muriatic acid and deal with the dangers thereof, most major tile manufacturers warn that acid could hurt the glaze on their tile, and will not honor any warranty claims as a result. it also tends to wash out the color from colored grouts.

    Additionally, most tiles have what's called a "cushioned" edge, meaning it slightly rounds up from the side edge to the face, and to fill that up completely will give you a much wider, ragged looking joint that most people just aren't happy with. Most tiles made today are MADE to have a slightly lower than flush grout joint.

    Nepotism is pretty common over there, compared to here, for better or worse.

    Believe me when I tell you-- there was no nepotism where my father was concerned. If anything, he was alot harder on me than any of the other apprentices working for the company. I got no free rides. As for the percentage of kids following in the father's footsteps, my stepson is making the forth generation of tile contractors in my family now, Starting with my grandfather, who was the first person ever to make a retail purchase from Laticrete even before they opened their doors. As for my "Italian accent rendition", I grew up with it, from family members as well as those at work, and if I wanted you'd never be able to tell that I didn't come over on the boat, so to speak. When I was working with the guys who trained me, I'd talk right back to them in the same accent (even with the regional differences) that they were speaking to me with. Like I said, I was a handful. :-)

    Sure, the ANSI thing gives guidelines for finished product, but no methods to actually accomplish that.

    Wrong. it's not a how to textbook, but ANSI 118 tells what materials should be used, and ANSI 108 specifies what installations methods must be used. As for LEARNING those installation methods, more and more people have been beginning to realise that there needs to be accredited teaching, because too many are learning improper methods, and sooner or later, the trade would be lost completely, otherwise. In 1980, thanks to my coming out of the military and needing an accredited apprenticeship program in order to take advantage of my GI Bill, my father and our local business agent for the Bricklayers and Allied Craftsmen initiated an apprenticeship program for the state of Connecticut. Since then, many other locals all over the country have also done so, including class time as well as monitored on the job training. Additionally, there are several places all over the country offering classes on tilesetting (NOT meaning Home Depot or Lowes, which aren't worth the time). The biggest of them is down in Pendleton, South Carolina, called the Ceramic Tile Education Foundation (CTEF), and they offer courses that range from beginner courses on up to training as an inspector. Additionally, there have been several good books written on the subject, so it IS becoming more and more a documented trade. Matter of fact, the two gentlemen I mentioned before-- one of them was the executive director of CTEF until a couple of years ago when he went into his own consulting business (Dave Gobis), as well as one of the best authors on the subject (Mike Byrne).

  • tuesday22
    Original Author
    15 years ago
    last modified: 9 years ago

    Okay, so "full" is out since it involves caustic acid. How about a step less than that, so just "fullER"? Any methods advised for fullER?

    That's interesting about ANSI. Every time I've looked at its content, my very uneducated eyes just see materials requirements (which is actually very helpful) and that sort of thing. The way to actually do whatever seems to be more an assumption of technique. Which, now that I think about it, is probably how it is supposed to be, considering that ANSI isn't written as a learner's manual. I suppose it should be assumptive of a base line of knowledge. (To me, it is just overwhelming.)

    Handful, huh? Yeah, it rather sounds like you cut a fairly wide swath, but thank God we all mellow, eh? (I've got some stories that, while not illegal or anything, I'm not anxious to repeat. Mellowing - and gaining humility - is a good thing.)

    By the way, I just found out that my mom has been using Elmer's Grout-in-a-Tube on her grout lines because, as she explains, "sometimes the grout falls out." And, she patiently adds, "It's no big deal, just like an inch or two of grout, not more than every couple months." So any effort I put into grouting my bath is, as you can imagine, fairly lost on her.

  • raehelen
    15 years ago
    last modified: 9 years ago

    Wow-

    I feel like I just stepped into a classroom!

    Thanks Tues for asking the question, and Bill, once again, you
    have been so generous with your time and knowledge.

    I've saved this thread under Renovations- Tiling, but truth be told, the more I learn, the more hesitant I become about attempting to tile on my own!

  • tuesday22
    Original Author
    15 years ago
    last modified: 9 years ago

    Our wall tile has the little baby bevel, but our floor tile has none - just dead square cut. I've made some practice boards but I can still feel the edge of the tile (no bevel)when the grout dries, which I imagine means there isn't enough grout, little curved divot from shrinkage notwithstanding.

    Hence my asking about fuller joints.

    I don't know if it makes a difference but the tiles are rectified porcelain where the color goes all the way through.

  • bill_vincent
    15 years ago
    last modified: 9 years ago

    No, it doesn't-- only when you're setting-- not when you're grouting. Without rubbing the tile with dry and burlap, you will not get it full enough not to feel the edges of the tile. I've tried. Trust me!

    raehelen-- It's all a matter of confidence. As the saying goes, whether you think you can, or you think you can't, you're probably right. Either way this thread could come in handy, whether you DIY it, or watch to make sure a pro is doing it right. Don't forget the FAQ's on the gallery side, either. They could be a big help in determining what questions you ask while interviewing potential installers.

  • tuesday22
    Original Author
    15 years ago
    last modified: 9 years ago

    Does the "dry and burlap" method *necessarily* demand muriatic acid? And do you actually mean "dry" or just very stiff? Is there anyplace I can read about this in detail?

    I read something called a field report from CTEF that talked about using cheese cloth. I didn't understand it, but it makes sense that cheese cloth would remove less grout from the joint than a sponge. It said something about lightly dragging the cheese cloth across the joint. Is this related?

    Short of that, do you think it is an absolutely mad idea to take a little bit of sand paper to knock down the severe edge of the mosaic? It isn't actually sharp, but if that edge is always going to be felt, I'm not sure that my bare feet are enthusiastic about the prospect. (I'm not suggesting anything dire, just hitting the edges a bit. And I have a lot of extra tile to practice on.) Is this insane?

    raehelen: Yeah, it's a lot, but you can break it down into little steps that are manageable. It is how you eat an elephant (one bite at a time).

  • bill_vincent
    15 years ago
    last modified: 9 years ago

    Does the "dry and burlap" method *necessarily* demand muriatic acid? And do you actually mean "dry" or just very stiff? Is there anyplace I can read about this in detail?

    Let me put it this way-- I've never seen a time when burlap and dry grout (and I do mean handfuls of dry powder) DIDN'T require acid cleaning afterward.

    I read something called a field report from CTEF that talked about using cheese cloth. I didn't understand it, but it makes sense that cheese cloth would remove less grout from the joint than a sponge. It said something about lightly dragging the cheese cloth across the joint. Is this related?

    No, this isn't related. You can also do a search on johnbridge.com in John's forum on using microfiber cloths in the same manner. It's a new twist on still another old method of grouting, which entailed using a sponge to loosen up the grout on the face of the tile and shape the joints, and then instead of using a sponge for the final cleaning, a well wrung out terrycloth towel would be dragged diagonally across the tile to clean it. Now instead, cheesecloth or microfiber cloths are used. Some are even swearing by these "shamwow" cloths.

    Short of that, do you think it is an absolutely mad idea to take a little bit of sand paper to knock down the severe edge of the mosaic? It isn't actually sharp, but if that edge is always going to be felt, I'm not sure that my bare feet are enthusiastic about the prospect. (I'm not suggesting anything dire, just hitting the edges a bit. And I have a lot of extra tile to practice on.) Is this insane?

    I personally think you're talking about alot of work for nothing, but then again, it's not my feet. If you're going to do this, you're going to want to go through several grits of sandpaper on a sanding block, and wedging the corner of the sanding block into the joint to knock down that edge, and then bring the finish back with the finer grits, going from about an 80 grit to about a 600 grit, or even higher. You'll see when you try it out on your sample.

  • tuesday22
    Original Author
    14 years ago
    last modified: 9 years ago

    Okay, let's put a pin in re-edging the floor mosaics for a minute...

    Obviously having wetter grout (to a point, obviously) is easier to get into the joints than stiff grout (ignoring the too-wet drawbacks), but wouldn't stiff grout shrink less? Wouldn't stiff grout (yes, you'd really have to work it into the joints) at least mitigate some of the swale?

    I know putting too much water in the mix wreaks all sorts of havoc with the end result. What is the danger (if any) with having a stiffer mix?

    Off topic, but curious about this: on another post, someone talked about using the grout powder to figure out which color to use. Is the grout powder the same color as the installed-hardened grout?

    By the way, your generosity of knowledge, spirit, and time is extraordinary. I've seen your name now on bunches of boards, all with extensive, explanatory replies. Extraordinary.

  • bill_vincent
    14 years ago
    last modified: 9 years ago

    but wouldn't stiff grout shrink less? Wouldn't stiff grout (yes, you'd really have to work it into the joints) at least mitigate some of the swale?

    It WOULD shrink less, which is why I suggested it with the unsanded grout at the beginning of this thread. It would NOT get rid of the swale in the grout joint,though. That happens as a result of washing the tile and shaping the grout joint with a sponge, and it's going to happen no matter how stiff the grout is, unless you let it start to set up too much, and then you'll have other bigger problems.

    Is the grout powder the same color as the installed-hardened grout?

    Not exactly, but it's closer than the color of the wet grout. It should actually be about a shade or two darker than the powder in the bag.

    And thank you. :-)

  • tuesday22
    Original Author
    14 years ago
    last modified: 9 years ago

    Okay. I think I've got at least a plan of action to try for the next couple days:

    1.) Try on a sample of floor mosaic to see if I can ease the edge. (Sounds more arduous than it might be, because the floor is unpolished, so the number of grits should be less than if I were trying this madness with the polished wall tile.)

    2.) Try a practice board with stiffer grout, acknowledging that there will still be some amount of swale (because of washing, and shaping, and shrinkage...heh, heh, I said "shrinkage").

    I'm okay with some swale (because I have to be AND it might maybe perhaps look weird otherwise, or at least, that's what I'm telling myself), but less swale is better than the alternative. Mitigating - not eliminating - is my goal, here.

    Stay tuned....

  • bill_vincent
    14 years ago
    last modified: 9 years ago

    tuning