Hi, I just remodeled our master bath and my niche has the thicker sill that matches the thickness of the countertop. I didn't even think about the thickness but now I do notice people usually do the thinner stuff for the sills. Oh well. I'm still happy.

I think whatever you decide will look good.

Either one works for all places INCLUDING the niche, or corner shelves (whichever you use). Usually it's determined by whatever slab is used for the vanity, because atleast on my projects, we match the stone pieces to the vanity top. So if the vanity is 2 cm, then so are all the pieces. Likewise for 3 cm. Here are a couple I just finished, one with corner shelves, one with a niche, so you can see the 3 cm works fine. Also, as you can see, I also like dog earing the niche shelves.

I prefer the smaller thickness myself as well.

The 1.5" stone is most times two pieces glued together and polished to look like one. When you order your stone you could ask them not to do this.

Or you could miter the tile in the niches like I do and omit the stone all together.

John, you mean the smaller for just the niche or for everything? 3 CM stone is two pieces glued together?

IF the 2 cm is available, I agree. Just that most times the vanity top is made from 3 cm stone, and usually they'll charge you for a second slab if you ask to have pieces taken out of a 2 cm slab to match. As for just mitering the tile in the niche, I did that around the other three sides in the plank shower I did above, but it's not my favorite thing to do, because it tends to leave a sharp, but weak edge that can be easily chipped. as for the shelf, There's a reason I went to using stone instead of tile for the bottom of the niche. That being that when the bottom of the niche is flush to the face of the wall, it tends to show soap drip marks down the face of the wall. With the stone shelves, I extend the shelf out about an inch past the face of the wall, to give what's called a "drip edge", so that any water or soap that falls off the shelf, falls to the floor, rather than leaving a streak down the face of the tile. And 3 cm is NOT two stones glued together. It's 1 1/4" solid stone. it's HALF again the thickness of the 2 cm stone.

No - Sounds like you have some metric slabs there.

3cm and 2 cm are metric slabs. Most slabs are 3/4" thick.

Sorry my bad.

3cm might be a tad thick for the shower niche. I would most likly use the 2cm

John, In thirty some odd years of dealing with slab stone in this trade, I've yet to ever see slab that ISN'T cut in metric measurements. Even in U.S. quarries. Yes, you can still measure slabs with a U.S. tape (and 2 cm can actually vary from 5/8" to 7/8"). But when it's cut it's cut to metric dimensions. Google it. Even 12x12 stone tiles are generally 30 cm.

What about the shower bench? Is 2cm a common size or do you prefer 3cm?

I think a lot of this comes down to the scale of the niche or bench etc. If it's a larger bench that runs the span of the shower for example - 3cm looks great. If you're talking a corner bench or something smaller - stick to the 2cm. Same goes for a niche - mine runs the entire length of the shower and I wanted a thick sill here for the look. If you're talking about a 14" x 14" square however, go with 2cm to save the space and match the size.