Flooring Tile - Wall and floor tile tear off and replacement

I also posted this questionson the JBS site. Just to be safe I am posting here also because of the server switch.

I will beginning shortly the remodeling of my downstairs bath. I will be removing existing wall and floor tile and replacing them with new tile. There is a stand alone shower in this room. None of the floors or walls are in a shower area.

Question 1. Should I replace the dry wall under the existing tile before I put up the new tile? If so, do I have to prime the green board before I tile? Do I have to mud and tape the joints?

Question 2. Under the existing floor tile if plywood. After removing the existing tile can I lay the new tile on the existing plywood? If not, what material would you recommend? The new floor tiles are 13x13.

If you can think of any other advice that might be helpful I would appreciate it. I have done smaller tiling jobs, like kitchen back splashes before with much success.

Thanks in advance.

Unless you really tweak the drywall during the tile removal
dont replace it, but patch any holes etc.
If you cant avoid really wrecking the drywall during demo
go ahead with greenboard(throw up a vapour barrier first)
Yep you should tape and one coat the board.Flexing at the joint without the tape could theoretically
cause dislodging of the tile.


You can lay tile on ply. Assuming the basement is concrete slab, and the plywood is connected directly on the concrete
Then you have a solid sub floor. The only concern with such a large tile, is,..crackosis. That's when the subfloor flexes and the tile, having such a large dimension, doesnt flex. It succumbs to crackosis, and of course....cracks
Not gonna happen in the basement.
On both the walls and the floor, I would use a tile mastic rather than a mortar base thinset.

good luck
ryk

Thanks for your input. The bath is not in the basement but rather on the first level. The floor is not on a concrete slab but on joists. Should I replace the top most layer of plywood with cement board?

Please advise.

Thanks.

George,

We won't shut down without answering your questions.

ryk,

Please stick to what you know. Everything you said here is wrong. Sorry to be so abrupt, but that's how it is.

Well heck, I'll stand by my response.
But it probably wouldn't hurt a bit to check out John's site
About removing the top layer of ply and replacing it with a cement board. Well, you must have at least a 5/8"subfloor (assuming the joists are correct dimension for the span and are at 16" centers)(3/4" thick for 24" centers). So, if you can discover the thickness of the lower layer of ply to be 5/8(3/4) or greater, you can use the preferred cement backer, hardi, durarock, wonderboard, they all work.
With a cement backer you can use thinset, if you mix it with 'acrylic admix'rather than water you will be adding bond strength and capacity to handle some flexing that a joisted floor tends to give. Also helps with a large tile, by adding flexibility to the bond.
Personally, if the 2 existing layers of ply total 1" in thickness, 7/8 is close enough ( gee I'm going out on a limb here) I would just go ahead and tile straight on the ply. A lot of guys dont like to go over ply, but then again alot of old-timey tilers wont touch backer board either (in certain applications)
The issue here is the tile size, as far as I am concerned.
Large tiles need a solid backing. Plywood is structural whereas cement board isnt. Bonding to cement board is superior, but with a 13" tile, I would be more concerned with the strength of the subfloor.

Find out as much as you feel you need to know !


good luck
ryk

Thanks for your suggestions. They are greatly appreciated.

Go to http://www.johnbridge.com. This is truly a 'mud room' of tile pros that will lay the advice on heavy. If you have tile installation questions you will get a straight answer. The pros will set you straighter than any tile you will ever lay. Just don't believe the stories about setting tile by candle light. Best regards.

Hey Twelvepole,

Who ever said anything about candlelight? Wine, beer, all that, but candlelight? :D