Simulations of indoor moisture generation in U.S. Homes

In residential buildings, there are many sources that contribute to the total hourly moisture generation, including occupants and their activities as well as some appliances. In cases of high indoor moisture generation, indoor air quality, building envelope durability, and heating, ventilation, and air conditioning efficiency can all be compromised. Oak Ridge National Laboratory designed a simulation tool, the generation of indoor heat and moisture (GIHM) tool, to capture the probabilistic nature of hourly indoor moisture and heat generation caused by residential building type, occupant behavior, climate zone, incidences of appliances, and other variables. In this paper, we focus on the moisture aspect of this tool. Results from the GIHM tool, as sets of hourly profiles of indoor moisture generation for specifically defined households, can be used as inputs for building energy simulation software, such as EnergyPlus. If many of these profiles are used as inputs, then the performance of an energy efficiency measure can be evaluated for the range of expected operating conditions in different homes. The GIHM tool can aid in designing heating, ventilation, and air conditioning systems that control temperature and humidity well, accessing the moisture durability of envelope components and understanding how different building designs and materials affect occupant comfort.