EQ Credit 7.1: Thermal Comfort: Design LEED-NC Credit: YES | UNSURE | NO Credit Intent Incorporate the establishment of a comfortable thermal environment for building occupants into the actual design process. Feasibility The designers of the new GSB should attempt to earn this credit. Thermal comfort is a key issue in the classroom setting, thus incorporating it early in the design process could have great benefits to the overall performance of the structure. Stanford’s mild climate and the abundant use of natural ventilation in the building also help the likelihood of earning this credit if accounted for early in the design phase. Analysis By using a psychrometric chart and the average dry and wet bulb temperatures for winter and summer in Stanford, indoor environment temperatures and humidities have been suggested. These can be found below.1 Summer – Dry Bulb: 86˚F, Wet Bulb: 66˚F

1 Psychrometric chart from American Society of Heating, Refrigerating, and Air-Conditioning Engineers, Inc., with modifications by JoAnna Billings

EQ Credit 7.1: Thermal Comfort: Design LEED-NC Credit: YES | UNSURE | NO The intersection point between the wet and dry bulb temperatures for the summer months occurs at a relative humidity of about 35%. Due to Stanford’s relatively dry climate, humidity does not seem to be an issue during the summer months. Natural ventilation could still be utilized at strategic points throughout the day (depending on temperature) without affecting the comfort level of overall humidity in the building. For indoor temperatures during the summer months, it would depend upon the ventilation and cooling system being used. In the case of natural ventilation, higher temperatures are often expected and accepted. The level of comfort would probably fall in the range of 72˚F to 80˚F for typically dry conditions in Stanford. Where chilled beams and ceilings are used, somewhat lower temperatures may be desired – perhaps in the range of 70˚F to 75˚F. Overall, however, controlled natural ventilation would most likely provide a comfortable indoor environment if controls are used to inform occupants of ideal times for opening windows. The cool, dry nights and mornings that characterize Stanford could greatly benefit the overall indoor environment. Winter – Dry Bulb: 34˚F, Wet Bulb: 30˚F

EQ Credit 7.1: Thermal Comfort: Design LEED-NC Credit: YES | UNSURE | NO The intersection point between the wet and dry bulb temperatures for the winter months occurs at a relative humidity of about 40%. This is slightly higher than the summer months. During the winter months, building occupants tend to wear warmer clothing, thus indoor temperatures can be slightly lower than the summer months. A comfortable range may fall between 66˚F and 72˚F for the winter. Heating is less of an issue than cooling for the Stanford climate. Sunlight could provide a heating source for the daytime hours, and use of thermal mass could continue to provide heat during the evening hours. As mentioned above, a notification system for the operable windows would benefit the comfort of building occupants by indicating when outdoor conditions are desirable to open windows.