I am using hydronic radiant heat under my travertine -- here is how it is setup in layers

Travertine
Thinset
Durock
Layer 1 plywood subfloor
Layer 2 Plywood subfloor
Slat Subfloor
Staple up aluminum fins with tubing snapped into them
Air gap
Reflective insulation
Fiberglass insulation

Amazing it works as well as it does after having to go through over an inch of wood, but it kicks butt!

I have the heating under the entire floor, including cabinets, but there is no food in them...

-- Andyman

I believe dcwesley is talking about the electric heating systems for directly below the tile.

Wires, Self leveling compound, Ditra, and then tile. Don't forget the thermostat sensor when putting the wires down! :-)

Using the self leveling concrete makes it an easy install. Just be sure you seal up any leak points before spreading it.

I will show my ignorance - leak points?

I don't know the details, but you need to read about using a heating mat over concrete. The concrete acts as a heat sink and therefore the heating is not as effective as it is over a joist/plywood/cement board type installation. I think there was alot of discussion about this on www.johnbridge.com. We love our heated travertine floors in our master bathroom - but decided not to heat the floors in our lower bathroom which were on concrete.

We did put the ditra down over the concrete - it was pretty easy to work with! good luck with your project!

"I will show my ignorance - leak points?"

The self leveling concrete is a bit on the soupy side and can find it's way through cracks or crevices in the floor (if not on a slab) or out through the doorway or anywhere it can flow if not sealed.

Yes - heating over a slab you will lose heat to the slab. I'm sure Bill has some experience with that. Maybe you can put down some kind of a thermal break? Or maybe it's not that big of a deal?

If I were you I'd check out the johnbridge forums for tile help.

Oh and yes, you don't put the mats under the cabinets. I also recommend a programable T-stat for your floor. We have one in our master bathroom, I have it set to come on before we get up in the morning then it is off during the day, then on again before bedtime.

It's not that big a deal.

Whoops, my bad. I thought you were looking for options :) Still, heated floors rock!

can i barge? we're installing travertine in a mudroom w/electric matt - which will also house a pantry (food storage). so we shouldn't place the matt under the pantry cabs or under cubbies/benches? ours is not a DIY but i like to know these things ...thanks.

No, you shouldn't. I think you'll find once you see the bill for the heat mats (both materials and labor) that there's no way you'd want to waste so much as a square inch of it.