This sounds pretty serious. I personally would make sure I knew all the options before proceeding with an expensive tile job that appears to have a high liklihood of failing. For one thing you need to make sure your joist size and spacing is sufficent. There is a calculator here: http://www.johnbridge.com/vbulletin/deflecto.pl

I would definitely also post this question over on the forum at the John Bridge tile site. You should get some good professional advice there. The resident tile experts come and go here, hopefully they'll also chime in!!

Lastly, if you go ahead and do mosaic tile in your kitchen, I would highly recommend using an epoxy grout like Spectralock. I used it in my latest bathroom. it is more expensive but it is much more impervious to staining, unlike traditional cementitious grouts that absorb stains and need frequent sealing. In a kitchen I would think that would be a big concern...

Here is a link that might be useful: Forum at John Bridge tile site

The first issue is can your house accept the higher kitchen floor?

With basic chicken wire in the middle of the mud thickness you're typically looking at 1-1/4" of mud thickness. Then the tile over that. Can your adjacent rooms handle the transition to a kitchen floor that's just had 1-1/2" added to it's height? With diamond mesh you can go thinner, but you'd still be approaching 1".

Other than that, floated mud floors are terrific. If he can do them, and is willing to do them, he's generally way ahead of the competition in terms of skill-sets.

The shape is not as important as how solid the floor is.

You could tie a trough with mosaic tiles and not have a problem if it was concrete.

Movement of the substrate is the problem, not its actual shape.

This is the reason I haven't done my OWN kitchen floor now, after 3 years. I have a 103 year old home, and there is some bigtime shimming needed in my kitchen floor. I also have a problem of severe seasonal movement, due to a stone foundation (I'm told).

One way or the other, before you do anything with tile to that floor, you want to have a structural engineer look at your house, and determine that the floor struture is stable. If that's the case, then you can level off what you have and tile it. if not, then he can suggest avenues to follow. Either way, you'll know for sure what you need to do.

Just looked at the joists, real 2x8's 16" on center no gaps for shims they are long....in fact they look like they are the total width of the home but supported at 10' from both of the outside walls with another beam running across the joists. Also the wood looks fantastic!!

TTT