# CIBSE TM59 Setup

To run a CIBSE TM59 simulation , an Airflow Network model is undertaken. This must be undertaken in Designer Mode.

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Once in Designer Mode, the first step is to enable the Airflow Network within your Model Settings. Next, apply local Airflow and Openable settings for your window and doors.&#x20;

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Modelling an Airflow Network can be complex. Although Better Building provides a significant amount of error checking to help determine if the model inputs are correct, it is impossible to account for all possible errors caused by violating network rules.
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