Development and Benchmarking of a New Whole Building Hygrothermal Model

During design process, building engineers evaluate the performance of various design alternatives in terms of their durability, comfort and indoor air quality, as well as energy efficiency using building envelope, indoor and energy analysis tools, respectively. But, usually the analysis tools are in the form of stand-alone package, where there is no direct link among them but rather simplifying assumptions are made on the other two when designing for one.

In this paper, the development and benchmarking of a newly developed whole building hygrothermal model are presented. The model considers the building as a system and accounts for the dynamic heat, air and moisture (HAM) interaction between building envelope components and indoor environmental conditions including HVAC systems, moisture and heat sources. The methodology adopted in this work is to develop and validate two primary models: building envelope and indoor models independently and couple them to form the whole building hygrothermal model. After successful integration of the models, the whole building hygrothermal model is benchmarked against internationally published numerical and experimental test results. The holistic model can be used to assess building enclosures durability, indoor conditions (temperature and relative humidity), occupant comfort, and energy efficiency of a building in an integrated manner.