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By way of background:

ZoneInfiltration:DesignFlowRate: This is the simplest infiltration model based on environmental conditions (wind and temperature).

ZoneInfiltration:EffectiveLeakageArea: This model is based on the Sherman and Grimsrud (1980) model, alternatively known as the “Basic” ASHRAE infiltration model, and would be considered an improvement over the previous model.

ZoneInfiltration:FlowCoefficient: : This model is based on the Walker and Wilson AIM-2 model (Walker and Wilson 1990), alternatively known as the “Enhanced” ASHRAE infiltration model. Of the three non-AirflowNetwork models, this model is widely considered the most accurate having undergone numerous validation studies by Lawrence Berkeley National Laboratory (LBL). But indeed, it takes more effort to calculate the needed coefficients from foundation type, presence of a flue, etc. This LBL publication has a lot of great information on calculating these parameters.

All three models have difficulties when trying to apply them to a multi-zone model. For example, how does one handle stack effect across multiple zones? How does one accommodate airflow between zones? These models can't really deal with many issues that are important for residential buildings. That said, in our BEopt tool (a residential modeling tool built on EnergyPlus), we do currently use ZoneInfiltration:FlowCoefficient. You could look at our implementation for more information.

Longer-term, we're looking to switch to the AirflowNetwork model to solve some of these issues and others. We're currently assessing the appropriateness of the model for residential buildings and are looking to make some improvements to the model next year.

By way of background:

ZoneInfiltration:DesignFlowRate: This is the simplest infiltration model based on environmental conditions (wind and temperature).

ZoneInfiltration:EffectiveLeakageArea: This model is based on the Sherman and Grimsrud (1980) model, alternatively known as the “Basic” ASHRAE infiltration model, and would be considered an improvement over the previous model.

ZoneInfiltration:FlowCoefficient: : This model is based on the Walker and Wilson AIM-2 model (Walker and Wilson 1990), model, alternatively known as the “Enhanced” ASHRAE infiltration model. Of the three non-AirflowNetwork models, this model is widely considered the most accurate having undergone numerous validation studies by Lawrence Berkeley National Laboratory (LBL). But indeed, it takes more effort to calculate the needed coefficients from foundation type, presence of a flue, etc. This LBL publication has a lot of great information on calculating these parameters.

All three models have difficulties when trying to apply them to a multi-zone model. For example, how does one handle stack effect across multiple zones? How does one accommodate airflow between zones? These models can't really deal with many issues that are important for residential buildings. That said, in our BEopt tool (a residential modeling tool built on EnergyPlus), we do currently use ZoneInfiltration:FlowCoefficient. You could look at our implementation for more information.

Longer-term, we're looking to switch to the AirflowNetwork model to solve some of these issues and others. We're currently assessing the appropriateness of the model for residential buildings and are looking to make some improvements to the model next year.

By way of background:

ZoneInfiltration:DesignFlowRate: This is the simplest infiltration model based on environmental conditions (wind and temperature).

ZoneInfiltration:EffectiveLeakageArea: This model is based on the Sherman and Grimsrud (1980) model, alternatively known as the “Basic” ASHRAE infiltration model, and would be considered an improvement over the previous model.

ZoneInfiltration:FlowCoefficient: : This model is based on the Walker and Wilson AIM-2 model, alternatively known as the “Enhanced” ASHRAE infiltration model. Of the three non-AirflowNetwork models, this model is widely considered the most accurate having undergone numerous validation studies by Lawrence Berkeley National Laboratory (LBL). But indeed, it takes more effort to calculate the needed coefficients from foundation type, presence of a flue, etc. This LBL publication has a lot of great information on calculating these parameters.

All three models have difficulties when trying to apply them to a multi-zone model. For example, how does one handle stack effect across multiple zones? How does one accommodate airflow between zones? These models can't really deal with many issues that are important for residential buildings. That said, in our BEopt tool (a residential modeling tool built on EnergyPlus), we do currently use the ZoneInfiltration:FlowCoefficient. approach. However, we actually model it via EMS in order to correctly handle interactions with duct leakage imbalance, mechanical ventilation, natural ventilation, etc. You could look at our implementation for more information.

Longer-term, we're looking to switch to the AirflowNetwork model to solve some of these issues and others. We're currently assessing the appropriateness of the model for residential buildings and are looking to make some improvements to the model next year.