Environmental Boundary Conditions for Long-term Hygrothermal Calculations ✓ Most Recent

This paper introduces a newly developed weather analysis computer tool, WeatherSmart. The main purpose of the tool is to facilitate the analysis of the outdoor weather data to obtain representative environmental boundary conditions. These conditions are, in turn, necessary for the analysis of long-term heat-air and moisture responses in building envelopes performed for thermal and moisture design. The environmental boundary conditions generated are location-specific and for the expected usage of the building considered. Several approaches to characterize either the indoor or the outdoor environmental conditions are part of the program. The different approaches allow analysis of the environmental conditions that apply moisture and thermal loads on the particular envelope component being studied. Construction-dependent and independent methods for selecting the outdoor moisture reference years have been incorporated in the tool. The indoor environment, representing the expected usage of the building under consideration, is derived by two approaches for both controlled and uncontrolled indoor environments. One case study performed using WeatherSmart to select outdoor moisture reference is presented. The case study represents an example of how the weather analysis tool is used to identify the outdoor moisture reference year for a particular location.

Authors: Reda Djebbar, Ph.D.; David van Reenen; Mavinkal K. Kumaran,Ph.D.

Citation: Thermal Performance of the Exterior Envelopes of Buildings VIII

Keywords: December, Florida, 2001