NRT Rob,

I have a radient issue concerning walls and floors as well. My issue is how to keep the radient heat in the floors and not moving to the walls. I will have ICF walls and a composite slab on steel truss floor system. I should also note that the ICF wall will have 4 5/8" of foam on the outside and 2 5/8" on the in side. With the majority of the foam on the outside, the 8" concrete core might be considered as insude the heated envelope. So on the mid level slab, a thermal connection is not so bad. My issue comes in where I have an outdoor patio, also slab on steel at the same mid level floor height. In the case of the patio, I will use a themal barrior/expasion joint. The issue gets more complex where the flat roof, slab on steel, connects to the ICF walls. The concrete roof will be insulated from the underside of the slab and will be used as a roof top patio. This makes the roof slab outside the heated envelope. I would like to isolate the roof slab from the walls. Have you encountered any questions like this?

Patrick T

The ceiling mounted radiant heating panels did the job for me.

Several companies make electric radiant heating panels that use long wave infrared heat to keep people warm.

The panels can fit on the ceiling or near the wall/ceiling joint or Cove.

Radiantelectricheat.com

aboveradiant.com

The new technology makes the energy use very efficient.  Allows zone heating. Low wattage and fast acting makes people feel comfortable at lower air temp.

TnVanMan