ICoSS Building Indoor Thermal Comfort Condition: 2012 Figure 6 shows visualization of Design Builder simulation of the present ICoSS building’s indoor environmental conditions (24 July 2012, 15:00). Note that as a green building no HVAC-based cooling is provided in ICoSS, and the building is clearly predicted significant overheating with its existing natural ventilation system on this summer day/hour. The simulation outcome confirms an earlier study of the ICoSS building during 2006-08, which reports a series of overheating problems in late spring and summer periods [9].