Building Envelope Thermal and Daylighting Analysis in Support of Recommendations to Upgrade ASHRAE/IES Standard 90: Vol 1, Parametric Study, Analysis, and Results

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Fenestration design can greatly affect the energy requirements for space conditioning and electric lighting in buildings. The net annual effect greatly depends on the effectiveness of daylight utilization with specific results being a complex function of the interaction among building design features, building operating characteristics, and climate.

The object of this study was to isolate the energy effects of fenestration and electric lighting design, quantify these effects, and develop simplified analysis tools for compliance use in the building envelopes section of ASHRAE/IES Standard 90.

In this study, envelope thermal conductivity, fenestration design, and electric lighting characteristics are parametrically varied through a wide range of values and in a diversity of climates. For these parametric variations, annual energy consumption is calculated with the DOE-2.1B energy analysis program. The numerical results are collected and stored on tape. From this data base statistical analysis is performed using multiple regression techniques leading to simplified correlation expressions among important building and climatic variables. These expressions characterize annual energy performance trends for cooling, heating, and cooling peak so that users can easily ascertain the energy implications.

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