Anyone with radiant walls?

Not walls like you asked about, but still a little of of the box when talking radiant heat, my father went with in-ceiling heat. From the attic down the material is like this. R50+ attic insulation, 3/4" strapping 16" OC,then 7/16" OSB, Tin foil with all seams taped covers the osb(this tinfoil continues down the walls as well),then there is 2x2" Strapping once again 16" OC, 1/2" PEX is attached to the strapping, this gives the tube a 1.5" gap between it and the reflective foil. Then another layer of 3/4 strapping, then finally drywall. There is a lot of material in Dad's ceilings but it heats the house beautifully. He went with some expensive hardwood flooring and did not want the radiant heat in the floor. Any floor that is tiled (kit/bath/porches) does have infloor though. Not to mention his outside walls are 2x6, and then a 2x4 wall is framed infront with the studs offset the best they can be (downside his window build outs are near 10") His wall insulation is R30+ and then there is an inch of tinfoil covered styrofoam on top of all this! Overkill? Maybe, but for the size of house he built I sure wish I had his heating bill!

In this order: GOOD--radiant walls, BETTER--radiant ceiling, BEST--radiant floor. Or you can do any combination thereof, to supply the BTUs needed for the calculated heat-loss of that space.

No experience with radiant walls, but I used Thermofin and 1/2" pex in a retrofit underfloor radiant install, and it is one of the best features about the house. The tile and wood flooring on the first floor are not cold, and the heat is nice and even. Water temperatures range from 80 to 145 with outdoor temperatures between 50 and -40F. My basement will have panel radiators when I do finish it.

Have done walls and ceilings as well. We did radiant in a tiled shower area in a custom house we built and did not need to install a door for this shower because the tile was nice and toasty warm. Works well. As they say, the devil is in the details.

I have several radiant walls in my house. They work reasonably well. I prefer radiant floors or panels if cost is an issue.

We did several radiant walls using different methods. In one of them we used Viega Climate Panel and did that ever work slick. Being that we could drive the temp of the wall much higher than a floor heating system, we only had to do the lower 3' of wall in that room. It would crank out the heat for sure.

I did a radiant wall project last fall. It works good. 1/2 pex on 8" centers, about 6' high. I am able to use 120 degree water to keep room comfortable. I am planning to add more where the floor is not practical and I have vaulted ceilings and may look at doing the lower 4ft of wall on my next project. I followed the plan in the Idronics book by caleffi.