It does sound like the tile's rectified. I'd let him go with it. If it's what we think it is, it's made to be used with a small joint. My only question is why he didn't use a small joint on the floor too.

I'm almost certain this is *not* rectified tile; it just has straight edges rather than uneven/wavy/scalloped edges that many tiles emulating natural stones have.

We're getting the tile tomorrow, so I can't show the tiles butted together; I have only one 6x6 sample tile I can offer a picture of:

This deserves my better camera and a muted bounce flash, but I only had I my little point-and-shoot handy, which puts too much flash directly on the surface and makes it look shinier than it is -- but hopefully it gives somewhat of an idea.

Bill, the floor tile isn't down yet, but he's probably going to start this morning. I thought there was always grout between floor tiles, and just wanted to keep the grout lines from being too wide and dominant, which is why I thought 3/16" for 13x13 tiles is what I've usually seen or read. Is the amount/absence of grout purely aesthetic and to even out minor variations in tile size for non-rectified tile? It has nothing to do with holding the tiles in place at all? Would you recommend butting them together on the floor as well, if the sizes seem to be very uniform?

Mongo, the tile is going on the floor and on the walls, floor-to-ceiling, in both dry and wet areas (alcove tub also used as a shower).

If we do butt the tiles close together on the wall and/or floor, does he then just squeeze (unsanded) grout in whatever small gap there is between the tiles?

Thanks for the quick help!

-- Eric

Eric-- First off, you're right-- that's not rectified tiles, and SHOULD have a bit larger joint-- minimum would be a strong 1/8". That includes on the walls in the shower.

But for those who DO use rectified porcelain (which DOES have straight square edges, usually with just a small chamfer on the top corner) and might find this thread in a search, you can NOT butt the tiles together and "squeeze" unsanded grout between them. It won't work. You need to have at the very least, a minimal grout joint of 1/16".

Thanks, Bill. That confirms what I thought. (Out of curiosity, how can you tell from the picture that it's not rectified tile?)

So I can have an intelligent conversation with my contractor, can you briefly explain *why* there needs to be the amounts of grout you mentioned. I'm not doubting your sound advice; just wanting to understand better. (So when he says, "I've done jobs this way" and shows me pictures of past such jobs, I want to understand what's wrong with that approach and be able to guide him to do my job differently without coming off too arrogantly with my "Internet knowledge" versus his years of work experience!) Thanks again!

-- Eric

Because other than rectified porcelain, tiles are punched out with a press, and then baked in a kiln. During the baking process, the clay will shrink slightly, and not always uniform, causing sizing to the tiles. You need a big enough grout joint to account for that sizing, so that you don't end up with tiles touching each other, just to keep uniform lines. You won't see a 1/16" size difference (which is normal to find in any tiles OTHER than rectified porcelain, within the same box, not to mention the possiblity of not being exactly square) NEARLY as much with a 3/16" grout joint as you will with a 1/16" joint. In fact, with a 1/16" joint, you could very easily end up with your joints running out of alignment and no way to shift them back.

Thanks, Bill. I don't think I ever realized that the grout was basically just cosmetic, to even out the variations in tile sizes.

-- Eric

The reason I was asking about wet versus dry is that you could theoretically do decorative "dry stack" in a dry area. I didn't know if that was the direction your installer was leaning.

But in a wet area you definitely want the tiles gapped and the gaps between the tiles filled with grout.

If you don't fill the gaps with grout, they'll fill over time on their own...with scum.

Tasty!

Mongo

Thanks, Bill. I don't think I ever realized that the grout was basically just cosmetic, to even out the variations in tile sizes.

That's one of its purposes.