What do I need for a subfloor

[Unregistered]

I'm going to remodel a bathroom, it currently has 2 lays of 3/4" plywood subfloor and then vinyl over that. I'm going to rip it out completely. I'd like to put down a layer of plywood or osb, then cover that with backerboard, then do ceramic tile. Can anyone recommend sizes for the osb and backerboard so I wouldn't have any problems with the tiles cracking or shifting? Thanks

[gsmurray24]

With two layers of 3/4" in place, you are in good shape already. However, after removing the vinyl, you'll likely need to put down another layer to smooth things out. I'd suggest a layer of 1/2" or even 3/4" plywood. You need to keep in mind the total height of this floor, with the added plywood and the depth of the tile. You might consider a marble saddle at the doorway. Anyway, with what you have already and adding a third layer of plywood, you should be very solid.

[Mr Fixit eh]

For help with ceramic tile questions there is no better resource than the John Bridge tile forum http://johnbridge.com/vbulletin/forumdisplay.php?f=1 I would have botched up my ceramic tile job badly if it hadn't been for these guys.

Although a few pros apply ceramic tile to plywood, almost all recommend cement backerboard. OSB - no way. You want to give special attention to the joists and joist span underneath the floor. Make sure that the subfloor is *not* nailed to the joists. You want to apply thinset to the subfloor and lay the cement board into the bed of thinset, then screw it down every 6 inches in both directions. You can use galvanized roofing nails if you prefer. If you use screws, buy the cementboard screws. They make a huge difference in the quality of the job.

Anyways, go to John Bridge for help from the experts. Also, he offers an inexpensive book on DIY ceramic tile. I wish that I had purchased his book instead of the one I got from the building center.

With tilework, it's all in the details. It's hard work, but if you enjoy paying attention to detail, you'll enjoy the results for a long time to come. If you don't, pay a pro and don't be ashamed. They earn their living!

Steve

[mdshunk]

I agree... go to the John Bridge forum site. They are the hands down experts on tilework. There's no place better that that site for tile and stone work. And yes, installing backerboard over OSB is a no-no.