Thanks for the responses. Look like I can't use the Geberit as my wall is 2 x 4 build, and there is no room to use 2 x 6. I'm not sure if having the tank inside the wall will be a maintenance issue. Probably a really dumb question... but I assume you would have to tear the wall apart if you ever needed to repair/replace the tank and associated parts? I'm somewhat hooked on a cabinet vanity. To me, pedestal sinks are not very useful... small bathrooms need all the storage space they need and pedestals don't offer any. But thanks for the links. I do like the design... I do have a primitive drawing but don't know how to upload to this forum. I have a CAD drawing but I've made so many changes to the original (which was approved by the city for permitting) that it would be misleading. The reason why I think a shallow 48" would be nice is that I can run it the entire length of the bathroom up to the shower partition... which I would like to tile up to about 40" or a few inches above where the vanity would end, and then glass up to 8" shy of the ceiling. From the shower partition, the shower is about 32" x 66". So it works well in the 7' x 5' 6" square box. Also, going with a long 48" vanity allows me to go really shallow. A very shallow sink/countertop is not as bad if it can be stretched out across a wider area. Total countertop/sink space is what I think people are most concerned with. I might try to find a really shallow sink/vanity... around 14" perhaps. Do you guys think 14" is too shallow for a sink vanity? This would allow me to go with a more standard toilet (round bowl) that hopefully offers dual/flush options. This is an urban zero-energy/smart home with water catchment so I need to go with the most water-sensitive models. I'm hoping to find a model that has a tall tank that will be a little tighter to the wall, now that I know an in-wall tank (e.g. Geberit) won't work. If I can find a nice 26" toilet and a 15" vanity, that will leave 25" of clearance between the vanity and the toilet... and I think this is reasonable. Oh, and the Neorest is very nice... but I'd like to keep my toilet expenditure in the $500-$1,000/each range. I actually need 4 shallow toilets for the project so I have to be a bit more sensitive to the price.

There is no such thing as a shallow P-trap, what your looking at is a "closet bend", which is simply a long radiu 90deg elbow.... IN Plumbing vernacular what you call a toilet is properly called a "water closet" and the round ring on the floor that the water closet is mounted on is called a "closet ring". From your description your closet ring is mounted directly on the top end of the closet bend, which is fine. If the drain line was deeper they could put a length of pipe from a closet flange to the closet bend, but in your case its not needed. Not only is there NO P-TRAP on the line, code prohibits installing a P-trap there. For a water closet the trap is built into the bowl section of the water closet and if one was to install a P-trap on the line, that would be double trapping which is code prohibited. The bottom line is,,, the answer to your last question if "YES", you are worrying for nothing.

I put one in our first floor powder room when we remodeled. DH did the work so I got a deal :-). I love the ease of cleaning - getting too old to get down on my hand and knees and wipe all the nooks and crannies. Planning to add one to the master bath too if that project ever gets off the ground. Only thing I don't like is our Toto wall hung - Maris. The water spot is too small and hard to hit. You know what I mean. I would order the Toto Aquia the next time and hope it doesn't have the same issue. We used the Geberit carrier.

I think wall hung toilets can be treated as a neutral design element. Keep the rest of the bathroom as you would have without the wall hung toilet and it will blend in fine. I looked up wall hung toilets traditional look and found a few that were more rounded and a bit less sleek than the standard. I would stick to Toto though. CORRECTION: I meant to say I would stick to Toto. I have Toto wall hung toilets and love them.