[jeffreyn]

In order to retile my bathroom floor, I've ripped everything down to the subfloor, which is made of 3/4" wood planks, not plywood. I would like for my bathroom floor to be as even as possible with the wood floors that run throughout my house, so I have about 3/4" to work with. I don't feel comfortable laying backerboard directly onto the planks, since it requires a layer of thinset, which would fall into the various spaces between planks. So, I plan to lay a 1/4" piece of plywood over the planks, followed by thinset, followed by 1/4" backerboard, and then more thinset and, lastly, 3/16" tile. I know thicker backerboard is recommended, so I have the following questions:

1) is my solution a bad one?
2) If so, can/should I lay the thicker backerboard directly onto the planks?

Thanks everyone! I've heard conflicting answers, and just want to make sure I don't have to do this all over again.

Jeff

 

[JazMan]

Jeff didn't get a reply right away so he asked his question in another thread;

It went like this;

Jaz, I'm having the same issue of wanting to keep the tile in my bathroom level with the wood floors in my house, but I don't want to lay hardibacker directly onto planks. I have 3/4" to work with, can I lay down 1/4" plywood, then 1/4" hardibacker, and then the tile (thin set included, of course)? Do I really need thicker hardibacker, or does my solution make sense?

jeffnc replied with this;

Thickness of the cement board doesn't really help you structurally. If I had 3/4" to work with, I'd put down 1/2" plywood (in reality, it's slightly less), then Ditra, then tile. This will give you a more solid underlayment than 1/4" plywood. It might be slightly more than 3/4" in total, but it will be close, and you'll need some sort of transition there anyway.

Then I replied with this;

Forget going for the same level, unless you wanna tile the entire house.

You need min. ½" ply over planks, and that's if the planks are in good condition. Do as Jeff said. install Ditra instead of Hardie ¼" which in reality will save you about 3/16".

So, 1/2" ply, which is 15/32 then Ditra which is ⅛" installed, then the tiles. Standard good quality tiles should be about ⅜" installed and you can tweak that a hair. But you'll want to finish the ends with a threshold or an aluminum "L" edging plus a gap that you'll fill with caulk.

Jaz