It works by circulating warm water through tubing under the floor. Unlike forced-air, it heats the entire floor and thus the entire room evenly — there are no cold spots or drafts. The heat radiates from the floor and gently warms the people in the room. Another advantage to hydronic radiant heat is that several heating zones can be built into the system. This means that if you’re not using a particular area of the house — the bonus room or the basement, for instance — the thermostats in those areas can be set to a lower temperature to save heating costs.