Ventilation Rate

Ventilation Rate is the minimum outdoor airflow rate required for the building to maintain minimum air quality levels. This airflow rate will be met at all operating hours.

The ventilation rate impacts the fan power design, so the higher the ventilation rate is, the higher the fan energy consumption will be.

You can use the Plugin slider to select a Low, Typical, or High outdoor airflow rate. Or, you can calculate this input for your particular project using this simple formula:



For example:



Note: 10 litres per second per person represents Medium/Moderate indoor air quality (BS EN133779:2007)

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    Michael Charleson

    If you have a building that is 50% natural ventilation and 50% mechanical ventilation does it affect the above calculation?