Thermal Comfort Model

Thermal comfort depends on six interacting variables: (1) air temperature, (2) radiant temperature (heat from surfaces), (3) air velocity, (4) humidity, (5) metabolic rate, (6) clothing insulation. Fanger's PMV model integrates these into a single prediction. The practical insight: comfort depends on far more than thermostat setting. A room at 72 degrees feels cold near large cold windows (low radiant temperature) or stifling if humid with no air movement. Each variable is independently adjustable, meaning you can improve comfort without changing air temperature—radiant heat panels, fans for movement, or humidity management.

When to use it

When a space feels uncomfortable despite normal air temperature, when trying to reduce energy costs without sacrificing comfort, when designing workspace environments, or when resolving disagreements about thermostat settings.

How it can help

Transforms temperature complaints from subjective disputes into diagnosable problems. When home or office feels uncomfortable despite the 'right' thermostat: check radiant temperature, air movement, and humidity. For home office: position away from cold windows, add a fan for air movement, manage humidity between 40-60%. For energy savings: radiant heating and fans are often more efficient than heating entire air volumes. Understanding six variables prevents the common mistake of addressing only air temperature.