A radiant heating system uses an efficient combination of hot water pumped through tubes to warm the floor. Unlike traditional forced air heating, where hot air blows to heat the air, radiant heat uses the principle of radiation to heat the surface. Radiant heats the occupants, not the space, and this is an important distinction. The result is a wonderfully comfortable and cozy feeling of warmth.
Comfort is the most compelling reason to consider radiant heat. Since the heat source is under the floor, temperatures are warmer at floor level (where you are) and the heat rises to the ceiling. Since the floor is warm, walking barefoot and sitting are the floor are cozy possibilities.
Since no air is pushed around, radiant heat offers a dust-free alternative for those suffering from allergies or asthma. Unlike forced hot air, radiant heating also will not dry out the air. Children are safe from contact with hot radiators or dirty vent ducts. Finally, a radiant heat system is virtually noise and maintenance free.
Answer excerpted from Eric Corey Freed's column on greenerbuildings.com. Click here to read more, and here to visit Eric's website, organicARCHITECT, where you can find excerpts from his forthcoming book, Green Buiding For Dummies.
The industry consensus
The industry consensus really limits that to about 85 degrees. A floor temperature that's much warmer than 85 degrees isn't comfortable to walk on. So, we try to design systems that produce a surface temperature of 70 to 80 degrees and not more than 85 degrees.
In-floor radiant and humidity levels
Please investigate your claim that forced-air heat dries the air out. Heating air up by whatever means doesn't change how much moisture it contains. The relative humidity changes as room temperature is raised, but that's independent of the heating delivery system. In heating climates, winter drying is mostly a function of air leakage/ventilation rate.
Radiant Heat Adds Resale Value Too
In our market, radiant heat can add $10,000+ to a home's resale value!