I am getting closer to being able to use this new bathroom! Putting tile backer on the walls behind the tub. 1.Is 4 mil plastic behind the backer board required? 2.For the seams of the tile backer board,is a waterproof membrane necessary on top of the seam tape and thin set? Seems expensive for a one gallon container.3. Should I run tile backer board all the way up to the ceiling behind the tub, or get close to the ceiling and then use MR drywall at the top? Would the drywall seam be easier to finish than tile backer board seam at the ceiling? Thanks for your input!
Finished the new bathroom and the tile work.I did not use 4 mil plastic behind the tile board, instead I chose to go the waterproof membrane material on top of the backer board. I ran backer board from the just above the tub flange to the ceiling. I used a waterproof membrane "red guard" on the seams and then on the entire backer board area,and then a third coat overlapping seams and second coat brushing and rolling in a different direction of the previous coat. Then I was able to start the tile installation. I had to make sure all backer board surfaces were flat and level in order to accept the tile and provide a flat finished tile installation. It went very well,because I took the time to do the leveling and waterproofing. The tile my wife picked out is a 12 x 12 porcelain tile with no pattern, I had some struggles tiling around the window, but it ended up very well.
Maura , thanks for asking. Here are the pics of the new upstairs bathroom DH (wkndwrnch) built. It's a wondrous thing. Standing at what used to be the outside wall of the house, looking into the new bathroom which was built on top of the wondrous new extension of the kitchen he created out of thin air on the ground floor. wkndwrnch, I am so blessed.