Good questions Jay. Yeah, don't put radiant in the garage floor, that wouldn't heat the bedroom (unless two zones were installed, one under the garage and one in the ceiling for the bedroom). The radiant system for this, would be incredibly simple: one heater, one pump and one thermostat. Because there would be flooring between the tubing and the bedroom space to be heated (which is a misnomer, because radiant doesn't heat air, it heats objects) I think the heat conducted upward through the plates and floor, becoming radiant heat in the bedroom, would work out fine. Because 110 degree circulated water, would give a comfortable 85 degree floor temperature upstairs. And a comfortable downward radiation into the garage, from the uninsulated joist bays. If I were Bob Davis, I'd put down 1 1/2" or 2" styrofoam insulation under the garage concrete floor, it'll make an unbelievable difference to the comfort level in there. I wouldn't want my garage too warm anyway. If the garage does get too warm when the radiant is running, I would experiment with insulating every other joist bay until it's just right. Place the thermostat in the bedroom, with an override in the garage for when you're working in there. TIP. Install an insulated garage door. Whew! that was a long one. Must go make a living. My best to you all. Brian.