cement board before tile? (basement floor)
Our contractor is in the process of finishing our basement, including a full bath area that is to be tiled. He has installed a cement based board on the bathroom floor and plans to tile over it instead of just tiling directly on the cement floor, which is the better way according to what I have read. What I have not been able to locate is any specific reasons why the cement board is a bad idea. Could anyone offer further information? The cement board is affixed to the floor with thinset and is also screwed into the floor at the corners. We have Dri-Core in the other areas of the finished space and the reasoning behind using the cement board was to raise the level of the bathroom floor so that it will sit evenly with the Dri-core. The cement board does say that it offers "Superior Mold and Mildew Resistance" and is made for wet areas. Any help would be greatly appreciated. Thanks.