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Energy standards and codes, including ASHRAE/IES Standard 90.1 and ANSI/ASHRAE Standard 90.2, have used cooling degree-day (CDD) and heating degree-day (HDD) values, and representative weather files, in the development and specification of criteria. Since the selection ofthe previous CDD and HDD values and representative weather files in 2002, climate data has become available for a more-recent period of record and for a more-extensive set of U.S., Canadian, and other international locations. The CDD and HDD values for individual locations and the representative weather files for those locations have changed, in some cases, markedly. Consequently, it was necessary to update the CDD and HDD values and the representative weatherfiles being used for the development and specification of criteria. This is the second paper in a two-paper series. The first paper explains how the CDD and HDD baseline values were updated and provided those values for the various climate zones. This secondpaper explains the process used to select representative weather files for the various climate zones, including the use of the degree-day-radius metric and minimum population thresholds. This paper lists three sets ofrepresentative weather files: global, U.S., and Canadian. [ABSTRACT FROM AUTHOR]

Energy standards and codes, including ASHRAE/IES Standard 90.1 and ASHRAE Standard 90.2, have used cooling degree day (CDD) and heating degree day (HDD) values and representative weather files in the development and specification of criteria. Since the selection of the previous CDD and HDD values and representative weather files in 2002, climate data have become available for a more recent period ofrecord and for a more extensive set of U.S., Canadian, and other international locations. The CDD and HDD values for individual locations, and the representative weather files for those locations, have changed, in some cases markedly. Consequently, it was necessary to update the CDD and HDD values and the representative weather files being used for the development and specification of criteria. This first paper in a two-paper series explains how the CDD and HDD baseline values were updated, including the use of population to inform the determination of the CDD and HDD baseline values. This paper provides those values for the various climate zones, including Climate Zone 0, newly established in ASHRAE Standard 169- 2013. The second paper explains the process used to select representative weather files for the various climate zones and lists those weather files. [ABSTRACT FROM AUTHOR]

Recent changes from manual to automated weather observing systems at most airports have introduced biases that influence building energy calculations. In particular, these biases compromise the accuracy of model-derived solar radiation. This paper summarizes changes in methods and instrumentation used to observe weather over the past decade, the consequences that these changes have on building energy calculations, and a new solar radiation model developed to help alleviate these consequences. This new model uses observations from the U.S. National Weather Service's Automated Surface Observation Systems (ASOS) to estimate global horizontal, direct normal, and diffuse horizontal solar radiation and allows for application to different climatic regimes while minimizing season-specific and cloud-condition-specific mean error biases. Model evaluation reveals that errors in solar radiation estimation are comparable to other contemporary solar radiation models. [ABSTRACT FROM AUTHOR]

The Equivalent Wall Method is applied to compare the thermal performance of concrete construction technologies against standard wood frame systems. The Equivalent Wall Method provides a technique to incorporate the multi-dimensional heat conduction steady-state and transient characteristics of an entire wall assembly, including the clear wall and wall detail regions, into a whole building energy simulation program. Several different types of precast concrete panel (PCP), insulated concrete form (ICF), and wood frame constructions were analyzed using this method. Whole building dynamic modeling was employed to calculate the energy savings of a typical single-family residence constructed with PCP and ICF systems compared to wood frame systems for six different US climates. Some configurations of concrete systems are shown to offer an improvement in performance over the wood frame systems, but the amount of improvement depends on, in decreasing order of significance, airtightness, insulation continuity, and magnitude and location of thermal capacitance. [ABSTRACT FROM AUTHOR]