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What are the best methods for grouting (and other grout issues)?

10 years ago

Do you thing there is something I could add to the grout to make it stronger on the edges? I've heard that adding acrylic paint can strengthen it (??)

No, not paint. That's just for color. There are acrylic or latex additives, called admix, which one can mix into dry grout instead of water for enhanced strength. It's sold on the shelves right by the grout. But don't add it to Polyblend brand. It already has polymer additives in it.

If your grout dries too fast, it's probably for three reasons. One, the base absorbed some water. Two, the ambient temperature was too warm, or you were working in the sun. Three, too much or too little water was added to the grout, or it was not mixed well.

I use Polyblend sanded grout with water. I've never done the misting bit, and unless you live in the desert, I'm still not sure why one would. I've never had a single crack or problem, so somehow, I'm doing something right. The last time I grouted, I made mental note of the steps. I call my technique "waterless" grouting, because the only water I use is that contained in a plastic Solo cup, so there is little to throw out, and nothing to hose down. I hope this will be helpful for someone, because it's as frustrating to me as it is to you that you are having problems.

I work at my kitchen table, over plastic garbage liners spread out flat, a big one for the table, and a smaller one for the project to sit on. Wearing a mask, I measure out the dry grout first, about two cups or a bit more. This is a great amount for a birdhouse, a bowl or a medium sized frame with some left over. Into a plastic Cool Whip container, I place about 1/4 of the grout, and spill in a good amount of water from my cup. I stir this very well with a painter's stick. It is very runny and very wet, but absolutely smooth. Now I start slowly adding more dry grout, stirring constantly. As soon as it starts to clump, I know it's time to add more water, a teaspoon or so at a time. This gets it smooth again, and still stirring, I add more grout. I keep slowly balancing water and grout, both in small amounts, until all the grout has been added. I work hard to get this completely mixed, concentrating on the bottom "corners" of the container. My grout is now mixed, and so thick, the paint stick stands straight up in it without support. But it is not dry anywhere, it is thoroughly and evenly mixed with no clumping.

I remove my mask, wait a few minutes, and lift a handful of the grout out of the container and apply it to my mosaic and start rubbing it in. This is the fun part! I lift up my mosaic to get sides, bottom edges of tiles, etc., spreading and rubbing as I go. I lift my mosaic with my left hand, and grout with my right hand only. I am thorough. When satisfied, I wipe grout from my hands with paper towels (those "shop" towels from HD are great!), wipe off the paint stick, pop the cover on the Cool Whip container, shake the fallen grout off the smaller liner, and go outside for a few minutes. Or...if I've spent a really long time grouting, I figure it's already time to start wiping (the not-so-fun part).

My initial wipe is with a dry paper towel. There is hardly any smearing, because my grout mixture is not a "wet" one. Now I move to a stack of clean "shop" cloths (aka "rags"), and begin serious cleaning. I dip a corner of the towel into the Solo cup water, and rub the grout away. I dip, rub, and turn the towel. By the time I've done two towels, the mosaic is clean and ready for the fine polishing.

This last necessary stage is tedious for me. I put on magnifying eyeglasses, get out my dental pick, and visually inspect every single tile, scraping away that last bit of grout from the edges. Unless all my tiles are level (ha!), I get little pindot holes. These I fill from my Cool Whip container. By putting the lid on it, the grout remains damp and usable for filling holes for hours! Last step is several white vinegar polishes, dipping a cloth corner, and keeping to the tiles as much as possible.

Now that I'm finished, I put the completed mosaic in the dining room to cure for three days. I wipe out the excess grout from the Cool Whip bowl with paper towels and toss. The grout, not the bowl. I use these bowls over and over, one for each grout color. I pour out whatever water remains in the plastic cup, and throw it out. (There will be a bit of grout residue in the bottom of cup, but that goes in the trash with the cup, not down the sink.) I swoop up the largest table liner, containing all my mess, and throw it out. I wash my hands, rinse them with vinegar and apply my favorite concentrated lotion.

Note how different my grout mixing process is from what I did when I first started, which was to pour all the grout in a bowl or bucket, and add water to the whole thing. My current process evolved because I found it too difficult to get a smooth mixture with water evenly distributed doing it all at once.

You folks are funny. Grout worms were an accident in the beginning. I had a container of premixed and some grout had collected around the edge under the lid and dried. It fell out when I removed the lid and I had my first grout worm. It was very helpful to get an idea of what that color would look like 'tween the china pieces, especially since they were all different colors and styles from a variety of plates. Looked good in some spots, not in others. So I made up little worms of all my other colors so I could lay them out on my pieces in advance. It's amazing how you can eliminate a color right away when you actually see it right up on the tiles, and also cuz grout dries a slightly different color. Also when you have grouts that vary only slightly (like white, off white, light gray, etc) it's easier to see what difference it makes. Has been so helpful for me I figured it's probably something everyone does.
Grout worms:
one tiny bit grout
one tiny bit water
mix together
when pliable, shape into tiny worm or worms
let dry

Place over ungrouted piece to see what "finished" product will look like.

More Grouting info:
Use only SANDED grout. Usually also named floor grout. Do NOT use wall grout. (unless your grout lines are less than 1/8", and even then, not all of them will be unless you are a master or have mosaicked on a grid! Wall grout will sink and crack in larger grout lines.)
Also please don't use premixed grout, it's results are not that great.

Mix enough grout for your project. You do not want to be trying to mix more in the middle. Grout is not a really expensive thing and more is better than less. The directions on the bag are for the whole bag so don't do that much (unless you have a whole floor or wall to do)! If you are doing that much make sure the one bag is enough. Dye lots do differ and you don't want to have patches of differing colour.

If you are adding colour, such as pure pigments or artist quality acrylic paint, then you REALLY must mix enough. You will never be able to match it exactly again (well maybe, but your measurements would have to be very precise, and even then...)!

Before you even start mixing you need to tape and protect any parts of the project that aren't to be grouted i.e. the back and sides or details like porcelain flowers or porous seashells.

Please avoid breathing in the grout dust, even an inexpensive dusk mask will provide protection.

Please also give yourself enough time to finish grouting your project. Once you start you can't turn back! Usually 2 hours is a good estimate! You will also need a pair of rubber or latex gloves, newpaper and paper towel or sponge.

Mix grout in a disposable plastic container. DO NOT DISPOSE OF GROUT DOWN A DRAIN! EVER!
Usually 1 and a half, to 2 cups of dry grout per sq. foot of mosaic are needed, but it depends on how far apart, and how deep your spaces are. If your grout lines are large, please mix more. Better to have grout leftover, than have to stop in the middle of a project to mix more grout.

The water you use! Best not to use tap water! I have never had a problem, but if you are using a darker grout, you may want to consider using a distilled pure water, with no minerals. Minerals (from hard water)can sometimes leach to the surface after the grout has cured, making it look like a much lighter grout, or it can become patchy.

Now comes the fun part!

Start with most of your dry powder in your container, then start adding water, a little bit at a time. The grout should be spreadable, and not runny. You want it to be like a batter, or nice for making mud patties.
The desired consitency depends on how porous your tiles or project are! The more porous, the more water they will soak up. An all glass project will not soak up any water, so the grout should be mixed a bit thicker. If you mix your grout to thin, or runny, it will not stay in the cracks, it will stink, and also be weak.

If you add too much water, you can add more grout powder. If you have added way too much water, you need to take some of the mixture out, and then add more powder, or you could be adding powder till the whole bag is gone! So be careful!

Then you need to let the grout slack for 10 minutes. Just let it sit and do it's thing. While it's doing this make sure you have everything else you need; gloves, newspaper laid out, paper towels or sponge.

Once you have it all ready to go take a nice handfull of grout and start spreading it all over the mosaic in many different directions so there are no air bubbles.

Keep working it all around your piece and when you think you've got it all in the grout lines start using your hand to wipe off any extra. But do not press down into the grout lines and remove any in the cracks, keep a flat hand and work off the surface grout only . This is also when you mold/bevel/sculpt the edges so it looks "pretty"!

Leave it for about 10 minutes and go back and gently wipe with paper towel or very mildy damp sponge, too wet and you will weaken and wash away the grout. Do this step as best as possible again without removing the grout in the cracks. You can fill in any tiny hole or spots that need more grout right now.
There will be a bit of a haze on the tiles. Let it sit for 15 to 20 minutes and then come back and gently buff the mosaic with paper towel or rag.

Come back in another half an hour and check to see if there is any leftover haze. You want to try to get this off before you leave it to cure as this could stay on the tiles for good!

If you are in a really dry climate, like i am in the winter time, be careful that the grout doesn't cure/dry too fast as it will crack. If you are finding your grout is cracking then you should mist

Vinegar will remove grout haze but you have to be careful with the colour fastness of the grout, especially if you are using a dark grout! Use a Q-tip and carefully individually wipe the tiles with the haze. the sooner the better before the grout is completely cured.It can be done up to a few days after you grouted. Or use Sulfamic Acid instead. You can get it at the hardware store and it comes in granular form. It is a mild acid you mix it with water. Always test for color-fastness of your grout first; like the back or a dot on the side of your piece, or even on the leftover grout. Made to be used with all kinds of grout. NOT sulfuric acid.

So at this pont you are pretty much done.... except for clean up which you can be doing while you wait for the grout to start setting. Remember NOT to put grout down the drain!

Posted by Haller Sat, Jan 22, 05 at 14:38
I recently grouted some smaller wall projects and was perplexed about how to grout them as they are somewhat 3-D with some tiles as thick as 2" (moulding-type edges) mixed with regular tile. Here's what I came up with and it worked so well, I am starting to use it for many of my projects. I think it would especially work well for those who don't have an outdoor or shop space and need to work in the house/keep things tidy.
In a nutshell, I put the grout in a plastic bag and piped it in like a pastry chef. I used a quart-size freezer bag and put my grout powder in, added some water, sealed it up and mixed it by squishing it around. Then I cut off the bottom corner of the bag and squeezed the grout out into my project. It worked very nicely... the key is to have the grout be the right consistency... soft enough to squeeze out but firm enough to hold its shape. After squeezing grout into all the cracks, I pressed it in well with my fingers and finished in the usual way, wet sponge, etc. Then I just threw the grout bag away... no clean up!

The only snag I had was that the ziplock is not quite strong enough for all the squeezing... it burst open on me (not fun). To resolve this I left enough room in the bag to close the ziplock and also put a twist-tie or strong rubberband around it. And it needs to be a freezer (strong, thick) bag... a thin sandwich bag will fail and make a big mess.