You are brave, I could never let someone tile anything, unless I was able to check the layout daily! I hate the look of 1/3 offset, so I prefer to go with stacked when there is no other choice. I find the repeating stair-step pattern busy and prefer the straight simpler lines of the stacked pattern. You need someone to do a scale drawing of the layout to get a feel for how the patterns will work. Next best thing is if the tile installer will prop some tiles up in the different patterns and take some photos for you. Match the grout to each tile color. Good luck!

Thanks for the replies! Good point about keeping things in proportion with a 12" accent - looks like three tile wide mosaic might be the way to go. I like both options, but was a bit worried that three tile wide looks a bit chunky. But keeping things in proportion seems like a good idea. Edges will be trimmed with those aluminium edges. There will be a niche, but due to the constraints of our townhouse (back wall of tub is a shared wall with next door and the left wall is an exterior wall), the niche will be on the right wall (where the fixtures are) and will be two smaller vertically stacked niches (I kind of prefer the niche to be less visible anyway, as then people won't see all my bottles :p). So the back tub wall will be flat, without any disruptions to the vertical accent. The door to the bathroom is on the right side (when looking at the tub) at the far end, so when you enter, you sort of see more of the left side first than the right - so I thought I'd put the vertical stripe off-centre to the left. RE waterproofing - my contractor has used DenShield with mesh tape over seams/joints/edges/nails and then RedGuard on top of that

I prefer horizontal on the walls as it seems more "natural" and "relaxing" (at least to me), to have them flowing around the room rather than pointing upwards -- particularly if you are doing a brick pattern -- and I wanted a horizontal accent stripe. When I think of rectangular tile, even large format, I think about bricks...and you wouldn't lay bricks in an upright orientation. However, if you are set on a vertical accent stripe, then it would probably look best with a vertical tile pattern. Or you could flip to horizontal, like I did. For the floors, the easy way is to do squares so that you don't have to worry about which way they flow. Here is a picture of my master bathroom, which has 12" X 18" on the walls, 12" X 12" on the floor of the shower, and 24" X 24" on the floor of the rest of the bathroom; my wall tiles are laid in a stacked pattern rather than a brick pattern: A couple of points: 1. My tiles were all dead flat, so I could have laid them in any pattern. However, many large format tiles have some slight bowing which can cause noticeable lippage when laying them in an overlap pattern, and this is usually emphasized by the down-lighting from the ceiling fixtures which creates shadows on the walls of the shower along parts of the grout lines. You can test for bowing by putting pairs of tiles face to face and see if there are any gaps or rocking at the edges, or gaps (light) showing through the center. However, regardless of how flat they are, the best way to avoid lippage problems is by doing a stacked pattern because sets of tiles typically bow in the same manner (such as having a slight hump in the middle). The worst situation is if some of them are flat and some are bowed as you will have lippage unpredictably all over. 2. You talked about doing 2" X 2" mosaics on the floor, and that is about right for a standard drain in order to get the slope right, and have good traction from the grout lines. However, if you want to use a larger format tile on the floor, you can with a linear drain, either at one end of the shower or in the center because the floor can slope toward the drain in a flat plane. Here is my shower floor with the drain in the center: If you put a linear drain in the center, the total amount of slope the floor has to have is half as much as having it at one end. A large format shower floor also has the advantage of far fewer grout lines to keep clean, but it requires tiles that have a wet static coefficient of friction (COF) or 0.60 or higher so that there isn't a slipping hazard; the COF number should be on the box, or the spec sheet, or available from the manufacturer or distributor for the specific tile.

LOL, I knew about soldered copper, but had never heard "sweat". I learned something new! Thanks. One plumber did not know they were hard copper and can't be bent. Not good... So, the connections/fittings will be soldered if copper, or they will be PEX. They will be under the concrete when lengthened. Both plumbers said that was not to code, but they didn't seem to care since no one will inspect inside the concrete. I just want the job done correctly, but it seems like it will not be to code. Thanks for your help. Now, I will know a little more about what the plumber should do. I have had 3 or 4 plumbers come here to do the work, then they change their minds I guess. They say they will call me, but I don't hear from them, and they don't respond to my calls. I found another plumber through my electrician, and he is supposed to come Tuesday. I can't believe this bathroom has been gutted since April, and nothing has been done yet. Southeastern Oklahoma used to have cold winters, but we rarely get past freezing now. Last ice storm was 2007.