NIST Multizone Modeling Website

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LoopDA Screenshot LoopDA is a natural ventilation design tool developed by the National Institute of Standards and Technology. Version 3.0 is an update to the original version 1.0 that was developed in 2003.

This software tool can be utilized to determine the size of natural ventilation openings necessary to provide airflow rates that satisfy design objectives based on minimum ventilation and cooling load requirements, for example as determined using the Climate Suitability Tool. The method employed is based largely upon the Loop Equation Design Method that provides for sizing of openings to utilize driving wind and stack pressures to achieve design airflow rates. This version implements a simple thermal design calculation to assist in determining design temperatures and airflow rates. A streamlined interface more efficiently implements the design process ( as compared to version 1.0). The documentation provides a design example that demonstrates how to use the software.