Wood floor questions

MalcolmReynolds

I want to tile my kitchen floor and I would like some advice regarding the existing wood floor.

Some details on the existing floor:

• 2 x 8 joists. 16" on center with a 9' span (this is approved for ceramic tile according to the Deflectolator)

• Bottom floor layer is 1 x 10 planks set diagonally across joists

• Next layer is 1/2" x 2" (actual size) T&G oak boards

• Top layer is linoleum vinyl flooring (glued to oak boards)

I would like to use the Ditra membrane for this job.

Some questions:
- Should I just remove the linoleum and set the ditra and tile on top of the existing 2 layers?
- If I leave the existing layers, should I put a screw in each oak board at every joist? (currently it is just nailed to the 1 x 10 planks)
- I have to remove a section of the oak boards that are badly warped due to water leaking from a dishwasher. Is it ok to replace the damaged boards with 1/2" plywood?

Thanks in advance…

cleveman

You should probably talk to the Schluter people.

Do you want to use Ditra because of a height problem?

Common sense would tell us that screwing or ring-shank nailing the oak into the floor joists would be good. The isolation membrane, which should not be attached to your joists, is the ditra.

You can replace the missing/damaged oak with 1/2" plywood. Make sure the height matches up.

JazMan

Hi Malcolmb,

As you said the joists are good for ceramic tiles.

Good decision about using Ditra.

1. No, you need to remove the hardwood planks too.
2. See #1
3. See #1

You may also need to remove the 1/2" ply. Probably should anyway on account of the 10" planks. Planks that wide usually require thicker underlayment cuz they may be warped or cupped. Then you'll see the condition of the subfloor, for possible replacement.

Jaz

__________________
Tile 4 You LLC Troy, MI
KERDI Shower Specialist ... DITRA Installs ... Product-Method suitability consultation. I have NEVER made a mistake, I thought I did once...........but I was wrong! - PRODUCTS ADVERTISED WITHIN MY POST ARE NOT ENDORSED BY ME!

MalcolmReynolds

JazMan,

Thanks for the reply. If I remove the 2" oak boards and the 1 x 10 planks are in good shape (no cupping, etc…) do I need to add a layer plywood? If so, what thickness?

JazMan

Absolutely you have to add and underlayment, you can't put anything over planks. You can't install any membrane or concrete backer board over planks. Gotta go over exterior glue ply or OSB. Look for exposure 1 rated or similar.

The minimum thickness you can use is 1/2", but only if the planks are as good as the day they were installed. Chances are you need thicker.

Jaz

__________________
Tile 4 You LLC Troy, MI
KERDI Shower Specialist ... DITRA Installs ... Product-Method suitability consultation. I have NEVER made a mistake, I thought I did once...........but I was wrong! - PRODUCTS ADVERTISED WITHIN MY POST ARE NOT ENDORSED BY ME!

MalcolmReynolds

Thanks again, Jaz…