Radiant Floor Heating System

Radiant Floor Overview

Radiant heating systems convert a floor into a large-area, low-temperature radiator. In most modern systems, warm water is circulated through closely spaced plastic tubing that is embedded in the floor slab or attached to the underside of wooden sub-flooring. Under-floor insulation is a critical component.Zoning depends on advanced manifolds that regulate flow or modulate the water temperature in different tubing runs. Sophisticated controls regulate all this – often with temperature sensors in the slab – in the rooms being heated and outdoors.

Adding up the Pluses

Radiant floor heating systems offer a wide range of benefits.


The large floor area warms people by direct radiation instead of heated air currents. Homeowners can walk around barefoot, even in the dead of winter – a very popular feature. Until you have lived with this form of heat it is hard to understand how comfortable it is.

Energy Savings

The floor’s radiant shine boosts the mean radiant temperature of a space and prevents temperature stratification. Proponents claim this allows homeowners to keep their thermostats lower. Someone normally comfortable at 72F would be comfortable at 68F without the usual hot and cool spots, offering significant energy savings. Another potential source of savings: boiler temperatures can be kept lower, trimming heat loss from the boiler and pipes. In addition, hydronic systems do not affect house air pressures; forced air heat, by contrast, can pull heat-wasting drafts through walls and ceilings when the supply and return pressures are not in balance.

Potential for Use of Solar Energy

The relatively low temperature of water required for radiant floor heating systems is well suited to solar water heating. In addition, the concrete slab can store daytime solar gains for nighttime use.

Quiet Operation

Radiant floor heating is very quiet, with no fan or duct noise and little of the gurgle and creaking sometimes heard in hydronic baseboard systems.

Flexible Room Layout

With no baseboard radiators and no floor registers, radiant floors do not restrict furniture placement or interior design.

Improved Air Quality

Radiant floors do not blow dust around as some ducted heating systems do. In addition, unlike electric baseboard systems, they do not use heating surfaces hot enough to burn dust particles, which can cause
respiratory irritation.

“The in-floor radiant heating system is much less drying than forced air during the winter months.”