the tile store recommended Custom grout

The last place you take advice from >Sales pigeons.

Here are two pieces of additional information:

1) Link to tiles:

Artistic Tile Jazz Glass

2) Here's what is listed on Artistic Tile spec sheet for the Jazz Glass:

Setting material: Mapei Adesilex P10/Keraply (is this the "adhesive" you ask about?)

Grout: Mapei Keracolor Unsanded

Grout Joint: As established in sheets

Membrane: Mapei Mapelastic AquaDefense

Caulk: Mapei Keracaulk Unsanded

Sealer: Not required

Cleaner: AquaMx Concentrated Stone & Tile Cleaner

THANK YOU!

This is a great point you have arrived at. Notice how the specifications dont mention wet area, or intermittent wet area....

Simple enough? not so much. Either follow the Glass MFG instructions or lose/void what they call a wrrty, the tile sales goon was gonna help you right out of that wrrty while making a fast sale and against the MFG instructions of the very tile they sold you..

Now the challenge is to find A tile professional that uses all the mapei products, if you vary or waiver from the MFG instruction and do have an installation issue the glass MFG has an opt out if any of their instrcutions were not heeded.

I will add that some of which is not TCNA compliant. so there is another conundrum in a shower build with unsanded caulk in a wet area.

Many MFG are vague about specific brands of adhesives/mortars, some glass MFG have had so many failures after install that they specify things a bit more definitively to protect themselves from ever paying out a claim.

Which leaves the tile professional to make hard decisions and in the end its the Tile installer that gives you a wrrty on their work. So what do you do now? search and search for just the right installer that will go Mapei, void TCNA rules with your job or do you Trust the wrrty and advice of your chosen tile proessional to make these decisions..

Hmmm...the spec sheet does say "yes" to "shower wall, including steam" so I believe we are okay for using it as a stripe down two of our shower walls, correct?

How hard is it for a tile installer to use a different product...if he has been tiling for a while is it still to be assumed that he would not be able to work with a different brand? Seems like the tiling part will be the trickiest part of this whole bathroom remodel...aaack!

I would use unsanded grout for glass tile.

OK for a steam shower, unsanded grout not epoxy or premixed. Mapei P-10 which is thinset designed for glass. All looks fine. I would be willing to use another brand of grout. ( although it would not be Custom) also be willing to use a different brand of glass mortar. You have the requirements if your installer wants to use his preferred setting material brands its fine as long as they are equal to or better. No need to make a mountain out of a mole hill. You have the information you needed. Present it to the installer and trust him/her from there.

If you would not use Custom, would you be okay using Prism? We are not making it a steam shower, was just quoting the spec sheet. Just a regular shower for us regular people;) Thank you for your comments.

Not familiar with Prism to give an opinion.

"Now the challenge is to find A tile professional that uses all the mapei
products, if you vary or waiver from the MFG instruction and do have an
installation issue the glass MFG has an opt out if any of their
instrcutions were not heeded."

WRONG. If you use another manufacturer's equivalent or better product, the manufacturer can't say a thing. They can RECOMMEND a manufacturer, but they can NOT demand that you use any specific manufacturer's products.

if you read what i said ..... it can be used by the glass MFG to their advantage in a wrrty claim!! relax

And you're not reading what I'M saying. It can't. If you use an equivalent product from another manufacturer, the glass MFG can NOT use it against you. No relaxing necessary. I just wanted to make sure you saw it.

Contemorganic-- Prism is a urethane grout that's actually a step UP in quality. The only problem with it is it has a very sharp sand in it, that may scratch the glass, and void your warranty. If you want to go with something that's a little more stain resistant than normal unsanded grout, Look into Laticrete's Permacolor Select (NOT just the standard Permacolor). The reason for the Permacolor is it's got a much finer sand to it, and won't be prone to scratching the glass. I specify the Select, because this is a new generation grout that Stone Tech's people had a hand in developing after Laticrete bought them out, and so this grout REALLY DOES have the sealer built right into it.

Contemporganic-- regardless of the BS above-- what you might do is look on Artistic's literature. I'm pretty sure they also list an ANSI spec to follow for the thinset and grout. That you DO have to adhere to, because that will tell you whether or not another manufacturer's thinset or grout is an acceptable alternative. That said, I've talked with the people at Artistic Tile before, and they WILL accept Laticrete's 254 Platinum, 255 nonsag, or GTA (glass tile adhesive) thinsets. They will also accept Permacolor grout. I've never called them about using the Select, but I don't see where there would be any difference. I would be nervous about using the Prism, though, for the reasons I mentioned above. If you have any questions on ANY of this, Artistic Tile lists their phone number on their literature. You can ask them directly. That will clear up any questions as to what advice you should or shouldn't take.

So although the comments became a bit of a side-dialogue, I thank all of you for your comments and input. I will review it all this weekend and make some phone calls to my installer and the local supply store to discuss best options and make decisions. Have a lovely weekend!