Don't really know how to word this. I don't know much about how the hydronic radiant works other then radiant warms objects, but is the floor the best place to run the tubing or are walls or ceiling/ blower about as efficient, I was just thinking about it a little bit, and the best ventilation for a spray room would be downdraft, but if heat was under floor wouldn't you lose it with downdraft airflow. Seems the most common place its run is under floor. Just thinking about how you would use it if using in a booth, but every booth I searched and found was electric radiant heat or forced air furnace. Or how bout just if you were using hydronic radiant heat in a room with downdraft ventilation how would you do it. from the ceiling, vent out the floor? Does any one have under floor radiant heat in there shop, and how do you ventilate it? I am Just thinking about for the future, wouldn't do anything anytime soon.