On Oct 23, 9:42 pm, Mikepier wrote:
A few weeks ago I asked if I could tile over oak floor area in my
foyer 4'X15' and everyone suggested using some kind of underlayment.
Recently my wife and I picked out a tile that is 1/2" thick and is 11
3/4" X 11 3/4". This tile looks a lot more beefy than ordinary tiles
and of course costs twice as much. Now the problem is because it's
1/2" thick it would be a problem heightwise even if I used a 1/4"
backerboard. So my question is will this tile be less likely to have
problems if I go over the wood floor because it's so thick even if I
screwed down the floor at every joist.
By the way my combined subfloor and hardwood thickness is 1 1/2".

The tile will likely be ok, but the grout will crack.

I recently did tiled two kitchen floors in a duplex. On the advice of
a tile pro, I put down ECB membrane, which is an antifracture
membrane, and I tiled over that. I had exactly enough membrane to do
both kitchens, and skipped a small area that would be covered by
cabinets. I tiled and grouted, and all the grout lines cracked in the
small areas where I hadn't used the membrane, in less than 24 hours.

JK