Curbless shower on below grade slab
I've looked at a lot of threads in several of the forums but nobody seemed to have exactly our situation, so I'm hoping to get some advice/feedback on our plans. Has anybody here installed a curbless shower on slab?
We are intalling a new, all tiled bath in our below grade basement (@55 degrees at floor all year). The room is interior to the basement, with no walls on the perimeter of the foundation.
We are planning for an infrequently used curbless (European style) shower, where the water just drains to the center of the bathroom floor. The main house drain runs right below this room anyway and the curbless arrangment offers flexibility missing in our smaller shower enclosures upstairs. The main purpose of this bath is to offer a toilet on a floor with entertaining space and a wet bar.
Inspector says as long as there is 30" of clearance all around for the shower the flooring situation is up to us, but of course we want some sloping toward the drain so water does not sit on the floor and mold.
Inspector suggested that our experienced tile guy can probably create the proper slope, while our concrete shower pan installer seemed to think we would need him to create some curbing against the wall to keep water away from the walls and to the create the proper slope. The shower head will be installed in the the corner of an 8' by 8' room. Do we need outside corner curbing to protect the tiled walls?
I also read on here that we may want to create a thermal break between the tile and the slab and even to install low voltage under floor heating on top of the thermal break material (cork, proprietary brands like Kerdi, etc.). This certainly sounds like it will make the shower more confortable to use, but there are no bedrooms in the basement and this will be the 4th full bath in the house, so we don't expect the shower to see a lot of use. Is thermal breaking and underfloor heating overkill? Could just running hot water work?
Headroom is an issue in this room so we do not want to raise the floor much as part of creating the slope and any other improvements.