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Question:

When tiling my upstairs bathroom floor, do I need cement board?

I'm pulling up the linoleum and replacing it with ceramic tile, 12x12. it's a small bathroom, on the 2nd floor.Under the linoleum is wood. Do i need to lie down cement board before I put the mortar mix down? Or will it be fine to put tiles on the mortar mix on the wood?

Answer:

You should have a backer of some type. There are a number of options available now so the choice is yours and dependant on the circumstances of your project regarding which one would be best. While many people do install tile directly over a wood sub floor that does not make it right. Tile has considerable permanence. It is somewhat involved to properly install and difficult to remove if the installation is not done correctly. The final outcome of a tile installation, like so many other projects depends largely on the preparation. So many people skip many of the necessary early steps that really do not cost that much extra but make a huge difference on the outcome. Use a backer system. G. Borders Home Repair, Improvement, & Handyman Service Plano Home Repair
May 11, 2017
To make up for that people place a lot, possibly too much, trust in cement boards. Cement boards increase the stiffness of anything away from the edge of the board. Tile that is set across to sheets have no more protection against movement than setting it on the wood itself. To a high degree it does work. There will be less cracks than the average wood floor. Of course you can get the same effect by putting a 1/4 inch or more of polymer modified mortar under the tile. Use unmodified mortar on cement board, modified mortar on wood for drainage and curing issues. A step up from heaping layers of rock, mortar, etc on the floor is a tile membrane. A tile membrane is a separation layer. It allows the floor to move without movement above it. It is very effective in preventing cracking if you follow instructions.
May 11, 2017
Cement Board Floor
May 11, 2017
Flooring plywood that is not laid down as tongue and grove (the whole floor) needs to be blocked at the edges. That means you will need to add solid framing lumber on all four sides of the patch. Securely attach them into the floor joists with nails. This is important because by cutting the plywood, you will have soft spots at the edges, which will cause your new tile to crack.
May 11, 2017
To begin with, I would pull up all the floor decking down to the joist, and make absolutely sure all joist are good. Once that's done and i have determined all to be good, i would lay down a 3/4 plywood. I would use a floor grade tongue and groove. You could use treated plywood, but its really not needed as long as you take all necessary steps during the remodel. After you lay down your cement board, make sure you grout the joints of the cement boards and allow to dry before applying thinset for the tiling, this helps to make moister barrier. make sure you seal the tile grout joints after laying the tile. make sure the sealer has ample time to dry. proper installation of the wax ring on the toilet is very important. make sure the toilet sits flat after installation and that it does not rock. use a good silicone caulk around the tub and the base of the toilet as well. you might also reseal the grout joints every year or so because alot of floor cleaners on the market can deteriorate the sealer. just a side note; if you can put a glass of water on the floor and when you walk on the floor and the water moves, the floor has what is call spring in it. all this means is that in time all the springing action in the floor can cause hairline cracks in the grout joints thus providing a channel for water. if this is the case then seal regularly. hope this helps
May 11, 2017

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