The plywood is water-damaged, so I need to replace it. The plywood is not original, either, but that probably doesn't matter. I also want to put down marble tile for the floor. What is the correct sequence? I'm thinking: 1x boards running diagonally, new, 3/4-inch plywood, concrete backer-board, and then the marble tile. Is this reasonable? Have I left out something?
Related to all this, the new floor is likely to be 3/4 - 1 inch higher than the old. I'm not entirely sure how, or where to make that transition. Should the step up be directly under the bathroom door, somewhat inside the bathroom door, or outside the bathroom door?
I did buy one book on laying tile, but as seems typical with so many do-it-yourself books, it overlooks all the hard issues, barely gives a mention to transitions. If anyone has a good book to recommend, I'm likely to go buy it.