Radiant heating is a technique to heat indoor and outdoor areas. In this kind of heating, surfaces including the skin and clothing are heated by the infrared rays emitted by the heater. However, the air in between does not heat up. The perfect example of radiant heating is the warmth of the sunshine. These are one of the most comfortable heating solutions available today. It is priced high because of its high efficiency.
Characteristics:
Radiant heating is known to provide heat immediately:

• A person in direct contact of the heater will get warmer faster, when it is turned on and cooler as soon as it is turned off
• In this case, the air isn’t directly warmed, however, it will warm up through contact with surfaces that have been heated
• The surfaces in a direct line of sight to the heater are only heated
• The intensity of the heat increases as the surface gets closer to the heater

Uses of radiant heaters :
These heaters can be useful for heating spaces with:

• short-term room occupancy (for example, in a bathroom)
• large size (for example, big rooms, rooms with high ceilings) to provide quick heat to its occupants
• fast air flow from the outside or other cooler spaces (for example, a basement)
• high transmission heat loss through walls or the ceiling or the floor (for example, a conservatory in winter)
• rooms with thermal mass (as the heater warms the mass)