Tiles on Wood Floor OK?

[christophergraber]

Hi,

I am planning on putting tile in my tiny 23 sq foot bathroom. It is a

1946 home in San Diego. I'm a first time tiler and it seems a bit daunting. From what I can tell by peeling up an edge on the current thin vinyl floor, it looks like hardwood floors under there - just like in the rest of the house.

So, if I put backer board (hardiboard, etc) down, then mortar, then tiles on top of that, the floor will be somewhat high compared to the rest of the house, I may need to chop off some of the bottom of the bathroom door, etc. Not sure exacly how high, but the smallest backer board is 1/4" and the 12" square tiles I just got are at least 1/4" thick I'm sure...

Is it ok to just use mortar on top of the wood floors (no backer board), so that my tiles won't be super high? Plus I want to istall a new toilet and I don't want it 10 feet off the ground, hahaha... Speaking of which, my old 1947 Kohler toilet has 4 screws instead of the standard 2 - not sure what's up with that?

Or do I need to tear out whatever wood floors are in there (not sure how thick that wood is) and install 5/8" or 3/4" plywood instead, put backer board on top of that, then mortar and tiles...

Suggestions?

Thanks

[Mikepier]

You can put tile directly over wood provided the wood is secure to the joists and does not flex, otherwise your tiles will crack. It should be

3/4" plywood on the floor. I had done this in my bathroom, and have no problems.

[bennet]

Good question. Unfortunately, the right answer is the hard way (isn't it always that way in home improvement?). Do not tile over hardwood floors, even if you use backerboard. It is not an adequately firm base for tiles. Your grout will crack. Make sure you have 3/4" plywood sub-flooring with no movement or squeaks. Then put on 1/4" backer board. Then tile.

BRW

[bennet]

Good question. Unfortunately, the right answer is the hard way (isn't it always that way in home improvement?). Do not tile over hardwood floors, even if you use backerboard. It is not an adequately firm base for tiles. Your grout will crack. Make sure you have 3/4" plywood sub-flooring with no movement or squeaks. Then put on 1/4" backer board. Then tile.

BRW

[Edwin Pawlowski]

Maybe, but there is some risk. . Depends on how solid the floor is. If you have flex, you may get cracks in the tile. Once you put in a good threshold at the door, it will not be noticed that the floor is much different. The toilet will be int he same plane anyway so that is not a consideration. You may have to extend the pipe though.

Not if everything is solid. Backerboard should be all you need.