Comfort Exceedance Metrics in Mixed-Mode Buildings

This paper presents an analysis of comfort exceedan ce based on thermal simulations of a mixed-mode building, across a range of climate conditions. Mixed-mode buildings are, by definition, hybrids along a spectrum from sealed HV AC to 100% naturally ventilated, and little is known about how building design and operation details shape their occupants’ comfort expectations. Using simulations of a mixed-mode building with radiant cooling, results indicate that there is a large difference between predicted annual exceedance values calculated using PPD and the adaptive comfort model. Calculated exceedance values are also sensitive to model assumptions about shell performance, solar heat gai n, thermal mass, and control precision. It follows that future work should be undertaken to be tter characterize measured comfort in mixedmode buildings in the service of improved building design and operation, more accurate comfort modeling, and the development of related codes and standards.

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