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Tile without cement board?

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Aug 11, 2013, 08:54 AM
Tile without cement board?
I am re-doing the floor in a small powder room. For reasons I cannot explain, the room itself is raised above the level of the hallway by about 2 inches and then has a separate raised area - maybe another 2 inches - for the toilet. :::I am guessing it was done to allow slope for the drains :::

I wanted to replace the old linoleum with tile, but I don't want to add the additional height of the cement board. The subfloor is plywood over - I believe - a 2x4 frame. Can I lay tile directly - knowing it will get very little actual traffic - or do I need to go with linoleum/vinyl again?

Thanks for any insight.
Aug 11, 2013, 04:35 PM
Is it really plywood?
Is it tonged and grooved?
How thick is it?
Is the 1/4 subflooring over it?
What's the joist spacing?

Aug 11, 2013, 06:42 PM
As Joe indicates, there are a lot of other factors that can affect weather your tile will stay down or not. What you describe is certainly unusual - my guess would be that you are correct in that some plumbing was moved around - but that it was done by an amateur who did not know enough to cut into the existing subfloor to reroute the plumbing.

Considering the above strange floor, I think it would be worth it to have somebody with some remodeling knowledge take a look to figure out what is going on. Then, if you want to invest into a slightly larger project, you could re-do both the raised floor and the jury-rigged plumbing correctly. Of course, this is not only more work but more money too.

If the existing raised floor is solid and you are OK with keeping it raised, then the best method would be to use Shluter ditra as a base material on top of the plywood.

It is also possible to put your tile on top of the plywood, it's just that odds are that the tile will pop up eventually.

Aug 13, 2013, 08:32 PM
Appreciate the help ... I am away from home, but will measure when I get back.
Aug 14, 2013, 04:16 PM
tape a flashlight to a dental mirror, get in the tub access panel, and look around.

it could be that there are laminated joists, which you can't poke drains and pressure pipe through, it would compromise them to the point of toothpicks. it could be that the joists were sistered to thicker lumber under the bathroom to take the weight of the tub and water. lots of possibilities.

the short answer is, put down the cement board or composite tile backing, and trim the door bottom if you have to. anything else and tile is likely to buckle or crack out the grout. you don't want to screw it down through pipe Wink if the subfloor is adequate, you can use 1/4 tile backing.

sig: if this is a new economy, how come they still want my old-fashioned money?