Combining energy, indoor air quality and moisture models for assessing the whole building performance

Abstract

In most studies, energy efficiency, indoor air quality and moisture performance measures are considered separately as a criterion of the building performance. Comparing the results of the energy efficiency, indoor air quality and moisture performance measures simulated by single model tools can have positive and negative interactions with each other. To provide realistic and comprehensive solution that calculates the impact of energy efficiency, indoor air quality and moisture performance criteria on the whole building performance, it is necessary to use a combined model. Therefore, in this research, a new model has been developed that combines all three e.g. energy, indoor air quality and moisture models. The advantage of this combined model is that in addition to predicting the performances of the building in the three areas of energy, indoor air quality and moisture, it will also be able to consider the impact of positive and negative interactions of these three criteria on the output results. Therefore, in combined model the simulated results show the actual performance of the building. The accuracy of combined model is verified using the paired sample t-test method. The development of the combined model has been performed in three phases. In the first phase, the feasibility of coupling EnergyPlus with CONTAM has been analyzed. In the second phase, the feasibility of coupling CONTAM with WUFI has been evaluated, and in the third phase, the feasibility of combining EnergyPlus, CONTAM and WUFI has been concluded. To analyze the differences of the simulated results by the combined and single models methods, four scenarios are defined for a case study of the three-story house. These scenarios include: 1- airtight fanoff, 2- airtight fan-on, 3- leaky fan-off and 4- leaky fan-on. To select the optimal scenarios, the ASHRAE Standard 90.1 for energy efficiency, ASHRAE Standard 62.1 for indoor air quality, ASHRAE Standard 160 and 55 for moisture performance and thermal comfort criteria have been used. Then, the results simulated by combined and single models for four scenarios are presented in the percentage differences with an acceptable level of ASHRAE Standards 90.1, 62.1, 160 and 55. The comparison of the results for the combined model with the single models have been performed for different climates of Montreal, Vancouver, and Miami. The results of this research show that the simulated measures by the combined model are different from the single models. The reason for this difference is that in single models, airflows, temperatures, and heating/cooling flow are defined as input data by the user but in the combined model, the control variables of airflows, temperatures and heating/cooling flows are exchanged in a cyclic loop between all three sub-models of EnergyPlus, CONTAM and WUFI. Since the accuracy of the combined model has been validated based on the paired sample t-test method, this new model can be used as a benchmark tool for the whole building performance analysis.

Date	11 Oct 2022
Original language	American English
Awarding Institution	École de technologie supérieure
Supervisor	Wahid Maref (Supervisor) & Hamed H Saber (Co-supervisor)