I've learned from this forum (thank bill v.!) that unsanded grout is used for narrow grout lines like 1/16 and sanded for larger. I don't know how the fact that the stone is limestone factors in. Is it honed and filled? Hopefully, Bill or another expert will chime in.

Hopefully Bill or some of the other experts will see this. I am not an expert, but I do know that sanded is much stronger and hold up better. I think it is intended for 1/8" or wider grout lines. For teeny grout lines, you have no choice but to use unsanded.

Thanks so much for the quick responses - I love this forum!

Eliz

Hi Eliz:

Post your question in the John Bridge tile forum. They are a HUGE help when it comes to all types of tiling questions. They were great help when we were doing our backsplash project. Good Luck!

Here is a link that might be useful: John Bridge tile forum

There's a difference in look because sanded grout has, surprise, sand in it that is visible. The texture is rougher and gives more dimension. Unsanded is pretty smooth and probably better used where the grout lines are thin.

As for strength, I'm a bit puzzled just because grout isn't going to add strength of any sort either way. The tiles better be set well in mortar to stand up. The grout is just to seal the gaps. If it cracks it's because there's movement in the tiles or subfloor, which is a problem with that, not the grout.

I'm curious about this as well. Eliz, please post your findings, thanks!

Non sanded grout for 1/8'' & smaller grout lines. Sanded for larger. Sanded grout is stronger and there's less shrinkage w/ sanded grout. (That's because the sand doesn't absorb any water that will then evaporate and shrink the grout.)

Thanks all. GC ended up using sanded (grout lines are 1/8") and the floor looks great. Will post pics in the next day or so when it's cleaned up.

Eliz

Great description Bill! Interesting that our grout lines for the backsplash will fall at the 1/8th mark like Elizpiz. Bill, you mention 1/8" or bigger use sanded. I noticed Cilantro mentioned 1/8" or smaller use unsanded. Our GC recommended unsanded. What do you recommend at exactly the 1/8 mark?

I'm guessing you'll say 1/8" should go with sanded...your instructions were very clear above. (Please don't yell!) Just want to double check. =)

We have large grout lines (about 1/4") on our shower floors and our installer used unsanded grout. Of course, it's cracking (and it's only been about 2 months). How should we fix this? Regrout sanded over the existing cracks? Or do we have to remove all of the unsanded grout and have the whole thing regrouted?

Thank you!
Keri

Hi Keri,

Sorry to hear about your installer not choosing the appropriate grout for your shower. Unfortunately, my recommendation would be to remove the unsanded grout before you re-grout with the correct sanded grout. The reason is more then likely there is not enough area that the sanded grout will stay in the joints properly. There needs to be at least 1/8 inch layer of new grout in the space to stay put and not flake or crack. It would be helpful to use an acrylic mortar admix liquid to the sanded grout which will make it adhere better.

Good luck!

This post was edited by TileExcellence on Sun, Jan 19, 14 at 22:11

We are doing restroom remodeling. Please help us on the following questions.

1. Restroom floor + closet floor(tile size: 6"x46", rectified): We want to use non sanded grout with 1/16 grout line. However, GC wants to use sanded grout with 1/8 grout line. He said it's more durable his way. But we really like small grout line for the look. Plus our floor tile is rectified. Is non sanded with 1/16 grout line durable enough for floor tile?

2. Shower room wall (tile size: 12"x24", non rectified): Same question. Sanded grout with 1/8 grout line VS. non sanded with 1/16 grout line. Which way should we go?

3. Shower floor (2x2 mosaic). How big the grout line we should use?

Thanks.!!

Aa Haa, all you experts! I am a DIYer. My grout line VARIES from 1/16 to 1/4!! But not a problem. I shall use sanded grout, and in special instances, pick out the sand particles. Or perhaps not! But in all seriousness, I have this problem, and I totally appreciate bill_vincent's cut-and-paste response above. I guess I will use sanded grout and just have to be extra careful when I am grouting thin grout lines.

I heard that sanded grout will scratch the finish of polished/honed marble/limestone.