We are progressing with our doorless shower. The wall is framed in. We have installed a Moen 3330 3-function transfer valve with a pipe extension for the hand-held slide bar. Please advise on whether this is the best placement for the valve and water supply. We're not sure if we should place the slide bar on stud #2 or #3 and where to put the water supply valve. We plan to use the hand-held shower to shower our daughter who is disabled. She will be seated when I shower her. We need to decide whether to install a corner bench in the back near the #3 studs or use a portable bench in the center of the shower closer to the # 1 stud. If we do the corner bench and place the slide bar on the #3 studs, I wonder if I will get soaked by the water coming toward me. The black line shows where the bench would be. If we go with the portable bench, we could place it in the center where the wall would stop the water from coming out. We could place the slide bar on the #2 stud so the water is flowing away from the doorway. In that case, should we move the valve a few inches to the left so the slide bar isn't as close to the valve? Would it look strange to have the power supply on one side of the valve and the slide bar on the other side? Since we can't afford to purchase the hand-held and slide bar yet, I can't experiment to see how it would look and if the hose would hang properly. Any advice would be appreciated. The bottom photo shows the type of hand-held shower head that I am considering. (I like the way it extends out unlike others that seem to stand up

Putting down XPS foam would also cause a impermeable barrier. XPS is slightly permeable, thus allowing water vapour to dissipate slowly. At the same time, it is unaffected by moisture and the R factor the XPS provides keeps whatever material is above it warm enough to avoid condensation from forming. It's not the vinyl that's affected--it's the adhesive that fails. This piece from Dr. Lstiburek details the problems of water vapour coming through a basement slab. (Though it deals specifically with improperly done slabs, the principles are the same.) Loose-lay vinyl may handle the moisture better. However, your floor will likely require extensive work to achieve a level bump-free substrate. Since you indicated some family members are more than 6'6" tall, I would suggest that tile over a crack isolation membrane might be the best solution. Or you could lay low-pile synthetic carpet without an underpad and just count on replacing it every few years. When I had rental properties, that's what I found myself doing because of tenant damage. Always lots of ends of lines, oddballs and returns available at discount stores and on Kijiji.

Oh yes, the old "But officer, I am legally blind and cannot see the speed limit sign, therefore I can drive as fast as I want." argument. And then we get "The federal govt requires me to pay taxes, so it is OK to rob the state bank to get the money to pay the taxes" argument. Or more specifically, the "It is OK to break other laws if I claim that I am asserting my rights" delusions. Why should a handicapped person be subject to, and have to contend with moldy and rotting subfloors just because they are handicapped? Building and designing a space for ADA does not give anyone the right to make excuses for substandard work or ignore building codes. ADA does not afford a person the right to a roll-in shower by any stretch of the imagination, or any configuration that does not have a reasonable expectation of containing and draining all the water associated with a shower. The designer must choose an option that meets both ADA and building code requirements that fits in the available space, or provide more space to make the design choice work for both ADA and the building codes. In this case, waterproofing and sloping toward the drain more of the bathroom floor to outside of any possible spray zone may have appeased the building inspector, but we have absolutely no idea of what the specific design is. You also can not ride 1/2 of a horse. You can not claim an ADA exemption for the shower, and then put a 2'-4" door on the bathroom and no clear space in front of the shower as required by ADA... or a 24" doorway into an "ADA" shower... ADA requirements only address those requirements that are specific to ADA. They do not, for example, address what size floor joist must be underneath the shower, or what type or extent of waterproofing needs to be done. If ADA was an excuse to not follow the building codes when inconvenient, people would be falling through the shower floors in short order. Both ADA and building code requirements must both be met. https://www.access-board.gov/guidelines-and-standards/buildings-and-sites/about-the-ada-standards/guide-to-the-ada-standards/chapter-1-using-the-ada-standards

How old is the slab? How flat is the slab? What's sitting on it right now? Let's start with the basics. Old slabs (built before 1990's) can have moisture issues. Without the right adhesives (and you would be surprised at how many adhesives that say they are 'unlimited' have rather sad limitations for moisture) you can get massive failures very very quickly. I'm always surprised at the 'glue down' the plywood and then nail down the hardwood. Why not just glue down the hardwood? It requires the same adhesive...so why not go ahead and do the hardwood that way...and skip the plywood. A floating hardwood floor (with proper moisture barrier underneath) is the one least likely to fail (due to moisture). A properly prepared slab (all the grinding/filling/leveling) is going to produce a lovely floating hardwood. And if you want a 'solid' feel underneath, go ahead and use a lovely 1/4" cork underlayment underneath the hardwood (but over top the moisture barrier). It is a really nice combination.