Achieving thermal comfort should be the goal of any home heating plan. However, this goal is often compromised by overlooking the fact that there are multiple factors which influence thermal comfort. Instead, a single factor – air temperature – is allowed to become the Alpha and Omega applied to the task of home heating. The jigsaw puzzle below graphically demonstrates the interrelatedness of the four environmental factors (blue) and the two personal factors (pink).
Heating the air is a fast and relatively easy way to add heat to the home. However, when only the air temperature is manipulated the following unintended consequences occur. First, the air in the home becomes stratified – hot at the ceiling cold at the floor. Second, heating the air does not increase the radiant temperature. Instead the disparity between air and surface temperatures in the home increases. This means a person’s body continues to radiate heat to the cool surfaces in the home even though the air temperature is warmer. The result is a cold and clammy feeling. Third, the stratification of air and the cool surfaces result in convection and increased air velocity (draftiness). Fourth, heating the air causes the relative humidity to drop lowering the apparent air temperature. Lower humidity dries out your throat and skin and gives rise to static electricity.
While radiantly heating surfaces in the home is slower it does not cause the unintended consequences that come with convective heat transfer. Radiantly heating surfaces in the home stabilizes the air temperature at a comfortable level, does not cause draftiness and does not dry out the air. Thermal comfort is increased resulting in a warm and cozy home environment.