Thermal Comfort
Core concepts
WELL v2 Thermal Comfort supports occupant satisfaction with temperature, humidity, and air movement. Preconditions typically address thermal performance, thermal zoning, thermal comfort, and individual thermal control. Optimizations include radiant thermal comfort, thermal comfort monitoring, humidity control, and thermal comfort education.
Thermal performance is the building envelope and HVAC capability to maintain conditions. Thermal zoning divides spaces by load and use so one thermostat does not serve a sunny perimeter and an interior conference room. Thermal comfort aligns with accepted comfort standards and considers air temperature, radiant temperature, humidity, air speed, and clothing/activity. Individual control lets occupants adjust local conditions-desk fans, local diffusers, or task heating-rather than only a central setpoint.
Traps
Do not confuse thermal performance with thermal comfort: performance is system capability; comfort is occupant experience. Zoning is not the same as individual control. Humidity control is separate from temperature control. A common error is assuming one open-office thermostat satisfies individual control. Another trap is ignoring radiant asymmetry-hot or cold surfaces-while focusing only on air temperature.
Rule of thumb
If occupants in one zone disagree about temperature, think zoning and individual control; if the issue is a cold window surface, think radiant comfort and envelope performance.
Worked example
A open office has one thermostat and occupants use space heaters. The project may fail individual thermal control even if the central HVAC meets setpoint. The fix is local control-desk fans, adjustable diffusers, or zoning-plus a policy on supplemental heating.