How do I prep subfloor?

gone_fishing · 05-08-2010, 09:55 PM

So we demo'd my kitchen today. We had 6 layers of linoleum/luan!!! Anyway, we are down to the subfloor planks. Do I put 1/2" ply on top of this then cement board the tile? What do I put down before cement board?

Thanks!

Bud Cline · 05-09-2010, 10:33 AM

Minimum 3/8" exposure 1 underlayment grade plywood.
Cement board in fresh thinset.
Tile.

tpolk · 05-09-2010, 10:37 AM

the first house we purchased to live in was a civil war log hospital with a 2 story balloon framed addition the log part had 15 layers. you could tell which patterns they liked or got a deal on cause they repeated

gone_fishing · 05-11-2010, 08:17 PM

Bud...right now we are 1/4" below the surrounding hard woods. If I understand your advice correctly I will put down 3/8" ply (Glue and screw) then 1/4" cement board. Tile will add another 1/4". This will put my kitchen floor 5/8" higher...I assume that's okay?

Second question...When I install the plywood do I want to go perpendicular to the joists and screw into the joists?

Thanks!

JazMan · 05-11-2010, 08:59 PM

Hi,

Bud's busy right now. (he may have gone fishing?)

3/8" underlayment grade is the minimum. NO GLUE. Fasten ONLY into subfloor planks, NOT the joists. So use screws that are 1/4" longer than the thickness of the two layers.

Tile will add a little more than 1/4" Hopefully the tiles a little thicker than that, plus the thin set. Figure 3/8" or so for the tiles. I recommend you use 1/2" underlayment plywood which measures a little less than 1/2".

Jaz

Jim F · 05-11-2010, 09:04 PM

And yes, it's going to be higher than your surrounding floor but that's what it takes to use tile. There are ways to transition the height difference.

gone_fishing · 05-11-2010, 09:06 PM

Jaz...thanks for the quick reply...1/4" or 1/2" cement board?

JazMan · 05-11-2010, 09:53 PM

Ditra.

It's more better....

Jaz