I plan to build a curbless (ADA roll-in) shower. I don't need to build up a curb or tile the entrance. Just as an FYI, I will never have a curbed shower again. It is a trip hazard and my friends that need canes/walkers/wheelchairs (some of them injured as children and young adults) cannot get past them. Limits resale to have a curbed shower. The curb itself is the problem, not necessarily the size of the shower. I think that is why most alcove/corner shower pans are being designed to be curbless on one side--makes it 'universally' accessible. Also, it is very easy to waterproof the entire bathroom floor these days. No curb or curtain or glass is actually needed, which saves lots of money and helps it dry out much faster!

Do any exist? I would rather have a cast iron, or similar pan; but cannot seem to find any in 36x36.

docket, I received your email, but apparently cannot reply to it because you have not enabled the email option. Here's what you wrote: I am seriously considering going with cast iron. I like the fact that it strong, I do not want to worry about leaks. It seems that w/ acrylic it is prone to get damgaged. Tile you have to worry about the grout getting black. The picture looks great how is the feel. Is is slippery? You still happy with your decsion to go w/ cast iron. Why did you go cast iron did you look at other options? We've been using the guest bathroom for some months now while work is being done on our MB and hall bath, so can tell you first-hand about the Kohler shower pan. It's very nice! Feels nice and solid underfoot, and not slippery at all. We recently installed two Toto cast iron tubs (one in each of the other two bathrooms); one bathroom is functional. I've been showering in there daily and the tub is very, very nice also. I really like it. Also, not slippery. We chose the cast iron because we liked how it looks, we liked the sturdiness and durability, and we liked the heat retention for which cast iron is known (and it was cheaper than a tile shower floor, which for a guest bathroom, was a good place to save a few $). We originally ordered a Kohler acrylic pan, thinking it was fiberglass. When it arrived though, we discovered not only was it acrylic, but it had no non-slip grips, which was a deal-breaker for us. We returned it for the cast iron pan. I really wasn't interested in a solid surface material (e.g. Corian, Swanstone), so never looked into those. Two things to note. One, cast iron can be a bit colder than other materials initially, but once you runs some warm-hot water, it warms up right away. Our guest bathroom is on the ground floor, on a slab, so it was a little chilly to the touch back in March (when we started using it daily). But, like I said, it warmed up quickly. The second thing, is that the non-slip grips can and do discolor. Regular cleaning with Lysol Basin, Tub, and Tile cleaner doesn't seem to remove the discoloration (at least not too well), however, the Magic Eraser (I use Mr. Clean original Magic Erasers) cleans them with little to no effort. They clean up so well, the first time I used it to clean mine, I thought I had scrubbed away the non-slip grips they were so clean and white! If I can help with any other questions, let me know.

You raise and slope the floor to drain with concrete before starting on pan. You can also hire a plumber to convert cast iron to pvc drain.