Gorilla construction adhesive will definitely hold it. I used it to adhere porcelain tile I ripped down to use as edge trim for my countertops to the 5/4 plywood

 

I think silicone would work.

 

I would use something else completely - simple vinyl quarter round that I would silicone to the tub.

You can use silicone against the tub, and if you think there's going to be a fair amount of water possibly leaking in there from water dripping from people or water splashing out, you can silicone the bottom edge against the tile as well. Or I suppose you could thinset to the bottom and then silicone the edge against the tub.

But that leaves the problem of grout lines. Again I don't think this is a great place for tile to begin with. Tubs usually expand and contract with the weight and heat of the water in them and will crack most cementitious bonds. One thing you could do is use the matching caulk to put in the grout lines.

 

Thats actually an outside corner trim. I would consider using a piece of synthetic “wood” moulding, one piece across the whole tub.

 

Thank you for the thorough replies.

@jeffnc tub expansion is something I am worried about, but do want to try to stick with tile or something nice looking to keep consistent with the rest of the bathroom's upscale materials. Do you think if I silicon it to the floor, and leave maybe an eighth to quarter inch gap for the tub, I could fill that with silicon, and it would be able to accommodate tub movement? I could use silicon that matches my grout color as well.

@Half-fast eddie this is a nice idea, but do you know if they make hollowed out synthetic wood quarter round? As you can see in my original post's picture, I cannot use a standard quarter round because the old floor would get in the way and stop it from sitting level on the new floor.

 

Do you think if I silicon it to the floor, and leave maybe an eighth to quarter inch gap for the tub, I could fill that with silicon, and it would be able to accommodate tub movement? I could use silicon that matches my grout color as well.

Yeah, but if you use grout in between the tiles it might crack. I personally would use white silicone against the tub, and the matching caulk (not silicone) in the grout joints and against the floor. So assuming you're using sanded grout, get sanded caulk in the same color.

 

When a floor or wall tile meets the tub you finish it with silicone, when your wall tiles meet in the corner you use silicone instead of grout.
I do not see the problem here, stick it in place with silicone and next day grout the lines between the tile.

 

https://www.lowes.com/pd/Royal-Building-Products-1-25-in-x-8-ft-Prefinished-Vinyl-Wall-Panel-Moulding/1000514791

 

Silicone to mount. If you look in the grout section or masonry section of a big box store they sell flexible grout in a caulk gun tube. Ive used it on counter to backsplash seams with good results.

 

Silicone to mount. If you look in the grout section or masonry section of a big box store they sell flexible grout in a caulk gun tube.

It's not really grout, it is simply caulk colored to match the various grout colors.

 

If you can't tell the difference between grout and caulk, you really shouldn't be giving advice.

 

That's ironic because we're both recommending the same thing, sanded "caulk" in a tube. But I call it flexible grout because Id never use sanded anything as regular caulk, only on tile "grout".

 

ha...ok