This credit is all about designing for thermal comfort, and then providing controls for occupants to continue to adjust conditions to meet their own needs.

Teams should prepare design calculations based on one of the three thermal comfort standards cited in the credit language. Calculations must take into consideration airspeed at the occupant level from air diffusers, metabolic rates based on activity, clothing levels based on seasonality and building type, and delivered air temperature.

When designing controls systems, split spaces up into regularly occupied individual and multioccupant spaces, since different types of controls are appropriate for each. Control strategies can include thermostats to adjust local diffusers, ceiling or desk fans, underfloor diffusers, or operable windows. Non-occupied spaces like storage areas can be exempt.

What’s New in LEED v4

• Two LEED 2009 credits have been combined into one credit: Controllability of Systems: Thermal Comfort and Thermal Comfort: Design.
• LEED requirements for natatoriums are now applicable for all rating systems.
• The referenced standard has been updated to ASHRAE 55-2010. The new version has useful expanded information on elevated air speeds for additional cooling and on using the graphic method. For an explanation of changes from the 2004 version of the standard, refer to ASHRAE Journal (June 2011).
• The credit now includes international standards to provide more relevant compliance options for non-U.S. projects.
• USGBC has established new compliance paths for data centers and warehouses. For data centers, the requirements should be met in regularly occupied spaces only. For warehouses, project teams should adapt appropriate specialized thermal comfort techniques for the storage and distribution centers, like fans or radiant flooring.