I have no idea why people wouldn't recommend a comfortable large built in bench for anyone - let alone for aging in place concerns. I had surgery a decade ago and a seat was recommended so I got a portable one. They are large and bulky and where do you put them if you aren't using them? Also makes it difficult to clean around. My bench is the width of the shower (formerly bathtub/shower combo) and a comfortable height. Why would one deliberately want a skimpy seat when one has the ability to get a safe large attractive seat. Also, one then has the ability to keep grooming needs by one's side when one is siting which is also helpful if one doesn't want to keep getting up and down to retrieve and put things away.
I don't know what the size of my bathroom is but the length is essentially a normal bathtub with a toilet next to it. There is a relatively narrow aisle and then the vanities run along the entire wall opposite the shower (that used to be a bathtub) and the toilet.
My experience with seniors (my father and friends and neighbors) is that most of them are not entirely wheel chair bound so they can manage to step over a curb even if it's with the assistance of a helper. My father needed a wheelchair in the last year of his life ONLY to go long distances but was fine with just a walker to get around inside. But obviously you don't want anything that would trip a person like bath mats or rugs.
It's hard to get a picture of my small bathroom but here are some shots. I changed the door so it swings OUT. Previously it swing in which blocked the shower and meant I had to close the bathroom door to access the bathtub.
This would be a shot of my bathroom looking through the door. The shower is to the right. The tall cabinet is in front of the toilet. There is a hamper on the bottom which is about the height of the counter and the upper portion has shelves.
I also had my vanities configured to maximize storage including a roll out under the sink so that stuff didn't get lost in the Black Hole of Calcutta.
This is a shot of the sink and dressing area. All of the doors including the sink cabinet have rollouts to maximize storage. I also had an insert which holds dryers and other tools installed in one of the cabinets.
I don't have a picture of the finished bench but here is a picture which shows the dimensions while it was being constructed. The top is a portion of the slab I used for the counter. Based on recommendations, you want a solid piece for the buit in bench just as you want a solid piece for the curb. My curb is relatively low and is also is covered with a remnant from my counter slab.
This is a picture of the wall above the bench - i.e. opposite the door.
It has the horizontal grab to assist getting up from the bench as well as safety moving around in the shower. It also shows the second hand held I installed which makes it very comfortable to access while sitting on the bench.
Interior of cabinet with roll outs
This is the roll out with slots for hair dryers and other tools. There is also a plug in there.
Another cabinet with rollouts
This is the roll out under the sink cabinet.
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