How do Floor Heating Systems Work?
Radiant heating works with thermal mass. This means that it heats the things around it, which then radiate the heat outward. So, for example, a heating cable will heat thinset and tile, then stop. And the thinset and tile will release that heat in the room.
Because thermal mass is very stable (unlike hot air from a furnace), radiant heat is much more efficient. You could open the windows in the winter but your tile floor would still be at 80 degrees. Once you close the window, comfort would resume immediately. With a furnace, it would have to kick in and work hard to replace the cold air with warm air all over again.
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