Flooring Tile - Best surface for tile ?

My kitchen currently has horrible looking and improperly installed (cracks everywhere) ceramic tile. The kitchen is built over over a crawl space and the floor was installed using wire mesh. The subfloor is T&G boards, it may have some sort of 1/4 inch material over that, and then the mesh. The entire structure is pretty sturdy. I am 99% sure the cracks in the current tile are due to improper installation (voids in the thinset, etc).

So my question is.....once I am rid of this floor and down to the T&G boards, should I install cement board or wire mesh.

If I go with 1/2 inch cement board, do I cement it to the boards and also screw it in, or are screws enough ?. Remember, the subfloor appears to be really solid. I've jumped all over the place and there is zero bounce. Again, the cracks in the tiles are most likely because of voids under the tile.

Thanks.

That installation technique (mesh & mud) has the highest failure rate of them all.

Once removed you need PLYWOOD. Then a tile backer of some type. But, there is more to this. You have experienced a failure and to duplicate the process you are taking out would be foolish.:thinker:

That installation technique (mesh & mud) has the highest failure rate of them all.

Once removed you need PLYWOOD. Then a tile backer of some type. But, there is more to this. You have experienced a failure and to duplicate the process you are taking out would be foolish.:thinker:



Obviously I am trying NOT to repeat the failure, therefore the questions about cement board vs. mesh. I think I'll go with the cement board. I guess you are suggesting plywood over T&G subfloor, then cement board screwed down to the plywood ?. Did I understand correctly ?.

Yes plywood over the t&g boards. Use 1/2" or thicker bc exterior glue plywood. Thicker plywood is always better if you can afford the height. Then you can use cement board or an isolation membrane over the plywood.

You have a failure there currently, possibly for a more reasons than one. You should make sure that your floor framing is strong enough to support a tile installation before you proceed any further. What size are the floor joists, what is their on center spacing and what is their unsupported span?:)

Yes plywood over the t&g boards. Use 1/2" or thicker bc exterior glue plywood. Thicker plywood is always better if you can afford the height. Then you can use cement board or an isolation membrane over the plywood.

You have a failure there currently, possibly for a more reasons than one. You should make sure that your floor framing is strong enough to support a tile installation before you proceed any further. What size are the floor joists, what is their on center spacing and what is their unsupported span?:)


The joists are at least 8 inches wide.......16 inches on center, and I believe the unsupported span is around 10 feet, 12 at the most. Like I said, I've jumped on the floor a few times, and I can see it is pretty solid....again......I am 99.9% sure the cracks are due to voids in the thinset.....I know this because I was able to pull up one tile and there was almost no thinset underneath.....

As far as total height, I have about an inch to 1.25 inches to play with including the tile, since I have to transition to hardwood floor, but I can probably fudge that somewhat.....so....1/2 plywood, then 1/2 inch backer board, then thinset and tile ?....that would put me about 1.5 inches, which may be too much....so I have to play with a combination of 1/2 inch and 1/4 inch.....so which should be which.....1/2 plywood and 1/4 inch backeboard (is Hardiboard good enough ?), or should I go the other way around.....thinner plywood and thicker backerboard.....


Thanks for the help.

1/2" plywood and 1/4" cement board.:)

or better yet, 5/8" plywood and ditra.

http://www.schluter.com/6_1_ditra.aspx

10' long 2x8's are ok, 12' 2x8's maybe not. So which do you have?

Plywood is always hands-down better than cement backer board. Cement backer boards offer no structural value what-so-ever.

How about 5/8" exterior grade exposure 1 plywood and then add DITRA? This bgrings you in at a little over 1" above where you are now.

http://www.schluter.com/2080.aspx

Thanks guys, I'll look into the Ditra option.

Started the kitchen renovation job today..........upon breaking up the ceramic tile, I found mesh loosely stapled to sheets of paneling of all things. The paneling was nailed (not glued thank God) face down to 3/4 inch plywood, which is nailed over something else. The plywood is in good shape except for 2 sheets that must have gotten wet in the past and have rotted.

I will replace the 2 sheets, then nail 1/2 inch Hardiboard to the plywood, then thinset the tiles in. This will bring me perfectly even with the hardwood flooring in the rest of the house.

Stay tuned.

3/4 inch plywood, which is nailed over something else.

What is the something else?

I will replace the 2 sheets, then nail 1/2 inch Hardiboard to the plywood, then thinset the tiles in. This will bring me perfectly even with the hardwood flooring in the rest of the house.

You will probably be ok with this. Cement board doesnt add any strength to the floor and the 1/2" will only serve to get you to the height you are looking for. A better solution would be 3/8" bc exposure 1 plywood and then ditra. The added plywood will add to the strength of the floor. The plywood and ditra will also put you at around the same height as the 1/2" cement board.:)

If using Cementboard, DON'T forget the thinset under it before screwing it down.:)

The "something else" is unknown until Friday when I pull up those sheets....there is a small hole in the plywood and I can see the "something else" below........could be more plywood. hard to tell as everything is distorted and discolored from getting wet long time ago (before I bought the dump I call home).

Tileman.....a buddy came by tonight to give moral support and he insisted on thinset under the Hardiboard, so I will do that. Any particular notch size I should be using ?.

1/4"x1/4" square notch for thinset under CBUs.:thumbup:

Thanks, Tileman.

ANyhoo......the "something else" turned out to be more plywood either 1/4 or 3/8. I have no idea why that thin layer would be the first thing laid in. The 3/4 inch plywood on top of it was totally rotted, but the thin plywood seemed to be in decent shape so I just put new 3/4 inch over the affected area.

Tomorrow.......my first crack at installing cement board. I may be on the evening news.......LOL.

Ok.......did about half the Hardiebacker today. Pretty easy. Set it in thinset with 1/4 inch square notch. Screwed it down tight. Beautiful thing.

Cutting it: used a grinder wheel and scored it pretty deep, and then snapped it. Also pretty easy. Get the right tool, use eye protection, and do it outside to minimize dust. I also found that if you have someone spray a water mist near the blade as you cut, there isn't a lot of dust then. The trick is to have a very fine mist so as not to get the board too wet.

I'll finish the backer board in the next 3 days or so, and then we'll install the tile. I'll post a series of photos when finished.