Redoing basement bathroom - need advice
I'm redoing a basement bathroom, and I had some thoughts and need some advice. First let me tell you about the bathroom. It has manufactured wood flooring, which is deteriorating in the bathroom from water exposure. I want to tile instead of wood, and since it is concrete under the wood flooring, should be minimal problems. However, on the walls the bath has some of that old, nasty, coated particle board that used to be common enough. But now looks ugly ugly ugly. My wife wants to redo more than just the floor while we are at it, and I agree, but I have to make some decisions. I also don't want to make my life complicated, as I am doing all the work myself.
Now you need some detail. I bought the house a few years ago. It was built in the early 70's, wood frame. The house is on a slope, and the basement is about half below grade. Poured concrete foundation. So on the back wall, where the bath is, the soil ends about 4-5 feet above floor level. The bath has a typical cellar window, about 14x28 or 30, something like that. Pretty standard - I replaced a couple of the 1974 originals when the glass broke, and it was a HD standard offering size. The basement was "finished", about 80%, probably about the same time the house was built. By finished, I mean it has wood framing against the concrete foundation inside, finished with sheetrock. There are two functional rooms and a "cellar" area where the furnace is.
I am in the northeast, so freezing winters are normal. When I bought the house, I thought the finished basement was great - and there are no known water problems. However, I have since learned that covering up a concrete foundation like this can lead to moisture buildup BEHIND the sheetrock - and mold. I've seen slight evidence of mold in the cellar area, but I keep a dehumidifier down there, and there are some holes punched in the sheetrock, high and low, which may have been done intentionally to increase the air circulation behind the sheetrock. So we haven't seen anything develop since we have been here.
I planned to tile around the tub area, which is next to the outside wall (and foundation), and under the window. I was thinking of using a concrete board to provide a good foundation for the tile - and I had an idea. What if I just knocked out the wall next to the foundation, and tiled directly on the foundation? It is concrete, after all. I realize it would be a little colder in the winter, but we aren't talking a very big area - the bathroom is exactly as wide as the tub.
Am I thinking I'm simplifying when I am actually making things more complicated? Will there be some drastic consequence I have not thought of? Is there something I should consider before I do this?