Stanford
University sought to retrofit two of seven recently built four-story graduate
dormitories (total project: 477,028 sf) that experienced
overheating problems. Loisos+Ubbelohde were commissioned to research possible
remedies for the existing buildings and to suggest design changes for future
campus housing. As designed, the building complex is cooled only by window
ventilation, and the windows do not provide sufficient protection from
excessive solar heat gain during overheated periods, such as a summer heat
storm.
We monitored the performance of the buildings during a spring break period,
installing sensors in typical rooms with varying orientations to record
indoor temperatures and relative humidity, with a weather station placed
on a nearby roof to record exterior conditions. The resulting data were
used to develop computer simulation models to predict interior conditions
with a variety of weather situations and architectural interventions.
Various remedies were modeled, including application of window film, exterior
shades, air conditioning and/or automated night ventilation. Each possible
solution was analyzed according to effectiveness, maintenance requirements,
speed of implementation, cost, occupant interaction and energy use. In
contrast to energy-intensive air conditioning, fan-assisted night-time
ventilation employing a technologically advanced thermostat to automatically
control room pre-cooling would use the building mass to modulate extreme
weather conditions. Design changes suggested for new buildings included
recommendations for effective shading, better windows that allow greater
ventilation, better glazing with a lower shading coefficient, higher insulation
values and ceiling fans.
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