A great place to understand radiant heating (or to explain it to your customer) is your local grocery store. Stop first in the gadget aisle and pick up a thermometer. It will probably read 70 degrees, a nice comfortable temperature. Walk up and down the aisles and keep your eye on the temperature. It never changes. No go into the frozen food aisle. Feel the chill? Check the thermometer. It’s still 70 degrees. What you’re feeling is a phenomenon known as Cold 70. It’s the feeling you get when the air temperature is 70 degrees but cold objects surround you. Your body gives off radiant heat to the cold surfaces and you feel cold. When you install radiant floors, walls or ceilings, you remove the cold surfaces and feel deliciously warm. Now go take your customer to the deli counter and stand in front of that chicken rotisserie. Just the opposite!