Older house, kitchen floor. There's 3/4 diagonal wood on floor joists after hardwood floor is removed. Can I put down 1/2 plywood/ osb and expect the ceramic tile and grout to last? 100% better to use cement board or that synthetic strand board?
Use the cement board. You may be able to get away with plywood if you were using an adhesive for attaching it, but if you use thinset, the wood will pull the moisture out of it and crack.
am i the only one who heard him say he wants a long lasting floor? ten years ago only the worst of hacks would use cement board on floors, i'm not even gonna talk about tiling on plywood. now everyone uses it on floors and they last about five years. what happened to mudding floors? lasts forever! much cheaper too. thought it was the rule! too many weekend warriors in the trades these days thanks to the home depot. what's next, perhaps a medical depot? mabye they'll start selling do it yourself surgery or cast in a can . sounds crazy but if it happened tomorrow you guys will be answering medical questions just as recklessly. stop reading labels as answers. don't any of you wanna see proof anymore? get real people. long lasting floors require tar paper, lathe, portland and sharp sand as a base. not cement board and certianly not glued sawdust or woodchips!
Plywood, yes. OSB, no. Backerboard, no... and here's why: deflection standards. The 1 1/8 thickness you achieve by adding a plywood subfloor brings it up to acceptable level. Common misconception in the industry that backerboard adds to the structural integrity, when in reality, its primary purpose is to provide a good substrate for the thinset to bond to. However, plywood is suitable if you use the proper thinset (important). Since the house is older, I would also recommend an anti-fracture membrane atop the subfloor.
OK I have to set the record straight here. So I hope I don t step on any toes.. 1/2 inch ply ( not osb) is a substrate you can use on flooring to use for tile. Must be well glued and nailed or screwed down. 6 inches or less on all seams and a minimum or 8 inches in the field. 1/8 to 1/4 inch expansion joints on the seams. No bigger no smaller. All seams must be taped w/ proper tape and thin set. I will agree that cement board is a great flooring substrate for tile but it is cheaper to use wood. This ply should be a 3 ply plywood not the common 5 ply. I ve used this method for 20 years and always used ATC codes . The use of proper thin set is a must also as a few others have stated.. Any questions you can e mail me. GL
I’m not crazy about applying ceramic tiles directly to a wooden subfloor, though lots of installers take this approach these days. From what I’ve seen, it's not unusual for installations of this sort to show signs of loose grout joints and occasional tile cracking. Ceramic tile is a very rigid material. Most ceramic tiles have very little tensile strength. In other words, if you try to bend or stretch a tile it will crack. Some wood floor systems, when designed to minimum standards, have too much bounce. This bounce will crack the tiles. for other information you can check my source site.