I am adding a basement bath to old bungalow. This will involve breaking through the concrete floor and tying drain and sewer into the main stack. I plan on a walk in style shower, and electric underfloor heat in the sink area. I am thinking about a euro style doorless shower design. The existing concrete floor is old (1930s) and not even enough to tile directly on top of. I am thinking about pouring a thinner layer of concrete and acid staining instead of tile.
Here are my concerns
1. Will concrete hold up as a floor material in the shower itself?
2. Would concrete be too slippery for a shower floor?
3. Perhaps a better solution would be to use a small threshold to separate the shower from the rest of the room, tile the shower, and concrete the rest of the bath?
4. Am I asking for trouble to pour on top of old concrete? Would a traditional concrete pan in the shower and thin set for the rest of the bath (and small tile) be a safer option?
Thoughts?
Replies
1. Yes, it holds up outdoors. But, its porous and, just like a sidewalk or wall will support the growth of algae, the concrete would, too, if not regularly cleaned. The surface will stay damp a long time, much longer than tile would.
2. Depends on the finish. It could be made not slippery.
4. Yes, you'd be asking for trouble.
Since you have to break up the floor anyway, how about removing the slab in the entire area of the new bathroom. Then you can place a new, solid slab of the proper thickness, with insulation underneath, and with precise leveling and sloping however you wish. Finish the concrete with a slightly rough surface (like a wood float finish) and tile with small porcelain tile. Or, tile just the shower and acid stain the rest.