Can't speak to NuHeat (others can) but I can tell you, unfortunately, NOT to go with ThermoSoft, at least...I know two of us here have had bad experiences with it. Both of ours worked for a while (as in were completely installed and covered with tile) and then stopped. Big PITA.

Thanks Flyleft.
The literature on these units imply that you just put the thinset over the heating mat, just like for regular tile laying. However, don't you have to adjust the rest of the floor (where you don't put the heating mat) to make it 1/8 inch higher? In my small bathroom only about 1/3 of the floor will have the mat.

Does this mean the installer has to glob a lot of extra thinset on the rest of the floor to bring the height up?

Can thinset be layed that thick and be effective?

Is it difficult to keep the tiles level? Is this a lot of extra work for the tile setter?

NuHeat is one of the better brands you can buy for several reasons, not the least of which being their customer service, both during and after the sale.

As for the thinset, there's quite a bit more time involved, being it should be buried one day (including feathering out to nothing) and then tiled over the next.

As for difficulty in leveling the tiles, it depends on how much time he spend burying the wires. If he just slapped them it, he'd going to have a nightmare setting the tile, especially if it's stone with a tight joint. Either way, it WILL take a little more time, though.

We love our Nuheat system. You can order custom sizes too.

I don't know how much of your floor you can actually walk on but, unless it's really just 1/3 of the total area, I'd reconsider limiting the mat to such a small area. Our mat goes everywhere including in front of the vanities, tub, linen cabinet, shower and toilet. Even so I occasionally step near the edge of something and you can really tell the difference. The tile is freezing where there isn't a mat. The heat does not radiate beyond the edge of the mat.

Bill, your remarks are an eye opener. The advertisements for these products imply it is little more trouble. I am in the middle of a remodel (professinally done) and didn't discuss this with contractor in advance. How many more labor hours hours do you think it would take to add mats and tile the floors for the following (as compared to tiling without heat mats):
10 s.f. out of 27 s.f in bathroom # 1
24 s.f out of 35 s.f. in bathrrom #2 ?

Thanks

We used Warming Systems radiant heat in our bath and kitchen. It's wire you tape to the floor and thinset/tile over. It took two of us 3 hours to do our large master bath, and it took me about 4 hours solo to do our kitchen floor.

It is trickier to thinset over, as you need to trowel carefully over top of the wire, so it took maybe 25% longer to do the troweling part on the floor.

I just tiled a 52 sq ft bathroom without radiant heat. It took me 6 hours, including setting Ditra underlayment, cutting and laying tile in the main room and a separate water closet room. If we had put radiant heat in, I estimate it would have added 2 hours: 1 hour to lay the wire and an extra hour in the thinset troweling under the Ditra. Plus there's the electrical wiring install of the thermostat on top of that.

I'm a DIY-er, not a pro, and I haven't used the mats, so YMMV.