Hi all, new to this board. I am renovating my kitchen and I had torn out the old vinyl flooring and the 1/16" backing for it. What I have left now are 3/4" thick by 3.5" wide wood strips as the subfloor (original subfloor when the house was built 60 years ago). I was planning on applying VersaBond bonding Mortar on the strips and laying 1/4" Wonderbord over that then screwing the wonderboard down. Is this a good Idea? I don't want to really tear out all the wood strips and start laying in new Plywood but if I have to I will. I drove screws into the wood strips next to the nails that were used to to secure them to the floor joist so that they wouldn't move. Thanks for any help.

Steve

I should also note that the kitchen is 8' x 11' 7" (aprox 110 sq/ft)

Steve

Hi
The wonderboard really doesn't have any structural strength, so adding it to your 3/4 floor is a bit under the minimum you need for ceramic tile. You should also have 2x10 joists, 16" on center. If you tie in the whole area with 3/8" exterior grade plywood, and then the 1/4" wonderboard, you would be right up to spec's. You can adjust for height differences at the door ways using a reducer strip. You can get some ideas here: http://www.schluter.com/english/products/2002/sectiona/renou/102-index.html

Hi Bri,

Thanks for the response! What I've decided to do (and what I am in the process of doing) is place 1/2" exterior grade plywood over the 3/4" wood strips to give it a nice solid surface. I’m attaching the 1/2" plywood to the 2X’s with Deckmate decking screws. What I am also going to do is lay out some bonding on the 1/2" plywood, lay the 1/4" wonderboard on top of that (while it's still wet of course) and screw the wonderboard down with Rock-On brand screws. I plan on then using Thinset on the wonderboard to set the tiles. The tiles will extrude a little more than 1/4" past my Oak floors in my dining room but i will fix that with an oak reducer. Luckily there are do doors in the kitchen and all cabinets (including wall) are out.

What do you think of this? I should also note that the tiles are Porcelain.

When I went to Home Depot they told me to lay 3/4" plywood on the wood strips then spread Flexbond on the plywood and set the tiles on that. I ran that Idea past an Uncle of mine who’s a carpenter and he almost took my head off! Told me that that’s the worst thing to do since once the mud dries it’ll release from the wood (since mud doesn’t stick to wood) and I would have a big problem with tiles popping out and also tiles cracking.

Hi
Sounds like a good idea...the 1/2" is even better. The wonderboard should be set in the thin set also(is this what you meant by bonding?)..it will fill any void you have under the board, and give you a nice solid surface. Thin set again of course for the tile.
The modified thin set will stick to plywood...but you are much better off using the wonderboard, since it is quite stable compared to plywood. It will expand and contract with changes in temperature and humidity. The wonderboard wont. You sound like you are under control. Let us know how it turns out...and come back again if you have more questions.

Actually the company that makes Wonderboard recomends VersaBond Bonding mortar. Should I use the thinset instead? So far I've read in two places (including the WonderBoard pamphlet) to use that. Any suggestions?

Hi
Versabond is thin set...it's what I use everyday..it's good stuff.

lol...I figured it was. I was looking to see if it said Thinset on it. . So that would also be good for laying the tiles in too then. Do I need to add any thing to it? I've seen "additives" for it in the store.

log in to the chat room...we can discuss it...but in case you don't....versabond is modified thin set..it has the latex in the bag...only water is needed for mixing. log in if you can..I'm there already.

why did you log out?

Question: Is the pre-mixed Thinset any good or should I stick with the stuff I have to mix? The drill I have is starting to take the punishment from all this Thinset mixing!

Oh and by the way I installed the new 1/2 inch plywood along with the Wonderboard. Tonight I just leveled any "dips" it had to a nice smooth surface, I'm shooting for this Saturady to install the tiles!