Meeting this credit in naturally conditioned spaces is tricky, because it’s hard to ensure that thermal conditions remain within the requisite range. It’s really only possible in a few specific climatic regions with especially temperate conditions.

Mixed-mode spaces have a better chance. That is, naturally ventilated buildings can still meet the requirements of ASHRAE-55 if heating and cooling systems can keep indoor conditions comfortable year-round. 

Certain spaces, such as greenhouses, gymnasiums, warehouses or manufacturing facilities often operate outside of the ranges defined by ASHRAE-55, which can put the project in conflict with designing either mechanical and passive systems that meet the credit requirements. If you have these spaces in your project, check with GBCI on whether you can earn the credit through an alternative compliance path. 

Regardless of the project type, considering target thermal comfort conditions—and designing to meet those conditions—early in the process is very helpful. 

A higher bar for coordination

While the credit requirements, and the referenced ASHRAE standard, have not changed from older versions of LEED, the documentation requirements for the credit are now more stringent. Completing the new LEED Online credit form requires greater attention to detail and more supporting calculations, which set a higher bar for coordination among team members.  

Different standards for international projects

International projects can choose to demonstrate compliance with ISO 7730: 2005 and CEN Standard EN 15251: 2007, or another local equivalent if appropriate. Those following ISO 7730 and CEN Standard EN 15251 should provide the same level of documentation to meet the credit, including PMV or PPD calculations and an evaluation of local thermal comfort criteria.